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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 22, Iss. 4 — Feb. 24, 2014
  • pp: 4590–4598
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Femtosecond imaging of nonlinear acoustics in gold

Thomas Pezeril, Christoph Klieber, Viktor Shalagatskyi, Gwenaelle Vaudel, Vasily Temnov, Oliver G. Schmidt, and Denys Makarov  »View Author Affiliations


Optics Express, Vol. 22, Issue 4, pp. 4590-4598 (2014)
http://dx.doi.org/10.1364/OE.22.004590


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Abstract

We have developed a high-sensitivity, low-noise femtosecond imaging technique based on pump-probe time-resolved measurements with a standard CCD camera. The approach used in the experiment is based on lock-in acquisitions of images generated by a femtosecond laser probe synchronized to modulation of a femtosecond laser pump at the same rate. This technique allows time-resolved imaging of laser-excited phenomena with femtosecond time resolution. We illustrate the technique by time-resolved imaging of the nonlinear reshaping of a laser-excited picosecond acoustic pulse after propagation through a thin gold layer. Image analysis reveals the direct 2D visualization of the nonlinear acoustic propagation of the picosecond acoustic pulse. Many ultrafast pump-probe investigations can profit from this technique because of the wealth of information it provides over a typical single diode and lock-in amplifier setup, for example it can be used to image ultrasonic echoes in biological samples.

© 2014 Optical Society of America

1. Introduction

In the discipline of picosecond ultrasonics, femtosecond lasers enable the generation and detection of ultrashort acoustic pulses on picosecond time scales [3

3. C. Thomsen, H. T. Grahn, H. J. Maris, and J. Tauc, “Surface generation and detection of phonons by picosecond light pulses,” Phys. Rev. B 34, 4129–4138 (1986). [CrossRef]

]. In order to go beyond the conventional picosecond ultrasonics experiments, we illustrate the potential of our technique by imaging picosecond time scale ultrasonic pulses propagating in a thin gold film. Usually, ultrasonic pulses are exploited for thin film mechanical diagnostics and for the measurement of linear acoustic properties of materials [4

4. O. B. Wright and K. Kawashima, “Coherent phonon detection from ultrafast surface vibrations,” Phys. Rev. Lett. 69, 1668–1671 (1992). [CrossRef] [PubMed]

,5

5. T. Saito, O. Matsuda, and O. B. Wright, “Picosecond acoustic phonon pulse generation in nickel and chromium,” Phys. Rev. B 67(7), 205421 (2003). [CrossRef]

]. In the present case, we demonstrate through direct visualization of ultrasonic pulse nonlinear acoustic reshaping during propagation which can be used in order to estimate the acoustic nonlinear properties of the material. Our results are a step forward in picosecond ultrasonic imaging over pump-probe scanning of the sample surface [6

6. Y. Sugawara, O. B. Wright, O. Matsuda, M. Takigahira, Y. Tanaka, S. Tamura, and V. E. Gusev, “Watching ripples on crystals,” Phys. Rev. Lett. 88(4), 185504 (2002). [CrossRef] [PubMed]

11

11. M. Hettich, K. Jacob, O. Ristow, C. He, J. Mayer, M. Schubert, V. Gusev, A. Bruchhausen, and T. Dekorsy, “Imaging of a patterned and buried molecular layer by coherent acoustic phonon spectroscopy,” Appl. Phys. Lett. 101(4), 191606 (2012). [CrossRef]

], far-field acoustic imaging [12

12. B. C. Daly, N. C. R. Holme, T. Buma, C. Branciard, T. B. Norris, D. M. Tennant, J. A. Taylor, J. E. Bower, and S. Pau, “Imaging nanostructures with coherent phonon pulses,” Appl. Phys. Lett. 84(25), 5180–5182 (2004). [CrossRef]

14

14. A. Amziane, L. Belliard, F. Decremps, and B. Perrin, “Ultrafast acoustic resonance spectroscopy of gold nanostructures: Towards a generation of tunable transverse waves,” Phys. Rev. B 83(7), 014102 (2011). [CrossRef]

], multi-channel detection [15

15. S. Bourquin, R. P. Prasankumar, F. X. Kartner, J. G. Fujimoto, T. Lasser, and R. P. Salathe, “High-speed femtosecond pump-probe spectroscopy with a smart pixel detector array,” Opt. Lett. 28(3), 1588–1590 (2003). [CrossRef] [PubMed]

18

18. E. Pontecorvo, M. Ortolani, D. Polli, M. Ferretti, G. Ruocco, G. Cerullo, and T. Scopigno, “Visualizing coherent phonon propagation in the 100 GHz range: A broadband picosecond acoustics approach,” Appl. Phys. Lett. 98(3), 011901 (2011). [CrossRef]

] or asynchronous lasers [19

19. A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, “Ultrafast time-domain spectroscopy based on high-speed asynchronous optical sampling,” Rev. Sci. Instrum. 78, 035107 (2007). [CrossRef] [PubMed]

21

21. E. Peronne, E. Charron, S. Vincent, S. Sauvage, A. Lemaitre, B. Perrin, and B. Jusserand, “Two-color femtosecond strobe lighting of coherent acoustic phonons emitted by quantum dots,” Appl. Phys. Lett. 102(4), 043107 (2013). [CrossRef]

].

2. Experimental set-up and methodology

A Ti-sapphire oscillator with an intra-cavity dumper running at a repetition rate of 500 kHz was used to generate laser pulses with a central wavelength of 800 nm and duration of 150 fs. The laser output was split into separate pump and probe beams. The probe beam was frequency-doubled by a second harmonic generation BBO crystal in order to obtain a probe wavelength of 400 nm. For imaging the sample surface onto the CCD, we used a ×50 Mitutoyo microscope objective, and a 20 cm lens placed before the probe beam-splitter in order to illuminate the whole CCD sensor, see Fig. 1(a). The pump beam of 15 nJ single pulse energy was focused onto the back of the sample with a ×10 Mitutoyo microscope objective producing a 2D gaussian laser profile at the focal spot with a FWHM (Full-Width at Half-Maximum) of about 10 μm, see Fig. 1(b). In order to avoid unwanted drift of the probe pointing during image acquisition, the pump beam is time delayed rather than the probe beam. The delay-line used in the experiment is composed of a Newport ILS-LM high speed linear motor stage of maximum speed of 500 mm/s controlled by a Newport XPS controller as shown in Fig. 1(a). This stage controller is a key aspect of the setup ensuring the electronic synchronization of pump modulation and image acquisition. The optical modulator is an acousto-optic (AO) deflector cell which deflects the pump beam with a deflection efficiency of about 90%. The disadvantage of using an AO deflector is the fact that it alters the beam quality of the deflected beam; thus, the 0th order transmitted pump beam is directed to the sample rather than the deflected 1st order pump beam. The TTL trigger sent by the XPS controller at a predefined rate (lower than the maximum frame rate of the camera) during the continuous motion of the delay-line alternatively switches the AO modulation on and off while the image acquisition occurs at each trigger. When the TTL trigger rate is set at f0, the image frame rate is locked at f0, while the AO modulation rate is locked at f0/2. This means that two successively recorded images do not carry the same information since one of them is recorded when the pump beam is present (the signal image) while the second is recorded without pump beam (the reference image). The reference image is recorded in order to sample the laser noise. Typically, laser fluctuations with the laser noise amplitude inversely proportional to the frequency dominate over electrical noise of the light detector. As a result, balancing the reference image with the signal image is used to drastically reduce laser noise. As in the conventional point pump-probe measurements with a lock-in amplifier, the signal and reference images should be acquired as close together in time as possible i.e. at the highest possible frequency. Thus, the ideal camera would have extremely low electrical noise and a high dynamic range in order to detect weak optical signals on top of a significant background (set close to pixel saturation for maximum detection capability), and fast frame rate for noise reduction. The camera we use is a Hamamatsu EM-CCD 9100-02, with high dynamic range (full well capacity of 70 000 electrons, 10 electrons of readout noise, 14 bit A/D converter) and maximum frame rate of 30 Hz at full image resolution of 1000×1000 pixels. Compared to CMOS cameras, CCD cameras have the advantage of low-noise electrical detectors, however, their frame rate at full image resolution is always lower than for CMOS [2

2. C. A. Werley, S. M. Teo, B. K. Ofori-Okai, P. Sivarajah, and K. A. Nelson, “High-resolution, low-noise imaging in THz polaritonics,” IEEE Trans. Terahertz Sci. Technol. 3, 239–247 (2013). [CrossRef]

]. Given the fact that the full image resolution of 1000×1000 pixels is not necessary in our experiment, a good compromise between frame rate and image resolution is given by an image acquisition at setting the image acquisition at 256×256 pixels for the image resolution while running the CCD at 101 Hz. The exposure time is set below 1/101 s and the probe light intensity is adjusted close to the pixel saturation for optimum sensitivity.

Fig. 1 a) Sketch of the femtosecond pump-probe imaging experimental setup. The ×50 microscope objective is adjusted to image the front of the sample surface by a 400 nm probe onto the CCD camera with high magnification. A 20 cm lens before the beam splitter is used to illuminate the whole CCD sensor. The 800 nm pump beam that excites the transient phenomenon is focused on the back of the sample by a ×10 microscope objective. The stage controller synchronously triggers the pump beam modulation and the image acquisition during the continuous motion of the high speed delay-line. After image processing, we obtain sequences of images showing picosecond time resolved evolution of the photoexcited phenomena. b) The pump beam is in focus at the sample surface where the light intensity forms a 2D gaussian profile with a FWHM of about 10 μm. c) The sample investigated here is a metallic multilayer structure composed of a 210 nm gold (Au) layer and a 30 nm cobalt (Co) layer coated on a sapphire substrate. The pump beam is focused on the back side of the sample at the cobalt layer while the probe beam is used to image the front gold free surface.

All the recorded images were processed by the following basic image treatment,
ΔII(i)=2(I2i+1I2i)I2i+1+I2i=ΔRR(i),
(1)
where I2i+1 is the 2i + 1-th image (a signal image), and I2i is the 2i-th image (reference image), both stored in the computer RAM. During continuous acquisition and motion of the delay-line, the computer calculates the result of formula (1) in real time which, for each signal and reference image pair gives the i-th image of the absolute change in light intensity ΔII(i), equals to the change of the sample optical reflectivity ΔRR(i). Because of the continuous motion of the delay-line during acquisition, the i-th index of the image is assigned to a certain time delay τ(ΔRR(i)ΔRR(τ)). The ΔRR(τ) images are directly scaled in absolute units, which is an advantage compared to standard lock-in detection techniques where the signal is usually scaled in arbitrary units. After each “acquisition run”, we obtain a sequence of images displaying the time variation of ΔRR(τ) over the desired time delay interval. The total number of images ni in the acquired sequence depends on the time delay interval, the frame rate of the camera and the delay-line speed. The sequence of “acquisition runs” is performed as many times as necessary in order to average the noise level of the ni images of the sequence. After N sequences of “acquisition runs” we obtained a smoothed time variation of the sequence <ΔRR(τ)>N, averaged over N runs.

3. Results and discussion

For the experiment, a hybrid multilayer sample structure composed of a 210 nm gold / 30 nm cobalt / sapphire substrate, depicted in Fig. 1(c), has been manufactured by RF magnetron sputtering (details can be found elsewhere [22

22. V. Temnov, C. Klieber, K. A. Nelson, T. Thomay, V. Knittel, A. Leitenstorfer, D. Makarov, M. Albrecht, and R. Bratschitsch, “Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons,” Nat. Commun. 4(6), 1468 (2013). [CrossRef] [PubMed]

]). The femtosecond pump beam is focused through the transparent sapphire substrate on the back of the sample at the cobalt layer. As a results of the strong electron-phonon coupling in cobalt, the laser excited electrons rapidly transfer their excess energy to the lattice such that the cobalt layer thermally expands and generates an ultra-short acoustic strain pulse propagating both into the gold layer and into the sapphire substrate. The excellent acoustic impedance matching between the cobalt opto-acoustic transducer and gold or sapphire minimizes the acoustic reflections at the surrounding interfaces (only about 10% of acoustic strain gets reflected). As a consequence, the initial shape of the acoustic pulse transmitted into gold follows the spatial profile of the laser deposited heat in the cobalt layer. Since the optical skin depth in cobalt at 800 nm wavelength is about 13 nm, the acoustic pulse profile follows the same spatial extension. After propagation through the 210 nm gold layer at the gold acoustic speed of ∼ 3.3 nm/ps [23

23. T. Pezeril, F. Leon, D. Chateigner, S. Kooi, and K. A. Nelson, “Picosecond photoexcitation of acoustic waves in locally canted gold films,” Appl. Phys. Lett. 92(3), 061908 (2008). [CrossRef]

], the laser excited acoustic pulse reaches the free surface of gold where it slightly modifies the optical reflectivity R through the acousto-optic effect and produces an image sampled by the imaging femtosecond probe pulse. Figure 2 shows the transient reflectivity <ΔRR(τ)> at five different time delays τ. The complete sequence with a total number of images ni = 150 has been averaged for N = 1000 times which corresponds to a total acquisition time of about 30 minutes. As a comparison, for an equivalent image resolution of 250×250, conventional pump-probe scanning of the surface sample would take about 250×250×5 s ∼ 5000 minutes (if we assume that one single acquisition takes about 5 s each), which is roughly 100 times longer than offered by our experimental technique. To further improve image quality and to diminish the uncorrelated pixel noise, a standard numerical filtering procedure using a 3×3 circular averaging filter has been applied to each individual image of the sequence. This numerical filter does not alter the image resolution (which is close to the diffraction limit) but only removes high frequency spatial noise and improves the pixel standard deviation (STD) from 5.1×10−4 to 2.1×10−4, see Fig. 2 at τ = 56 ps. The value of the STD (in the range ∼10−4) gives a reliable estimate of the detection sensitivity of the experiment, which is significantly better than required for this measurement. Increasing the number of averages N would improve the detection sensitivity by N, however it would critically augment the total acquisition time.

Fig. 2 After image processing, we obtain a sequence of images showing time resolved evolution of the transient reflectivity ΔR/R on a picosecond time scale. Here, we show selected images from τ = 56 ps to 83 ps after the pump excitation of the acoustic pulse - see the supplementary material online for the full sequence ( Media 1). In the present case, the arrival of the laser excited acoustic pulse from the cobalt layer at the gold front surface slightly modifies the gold optical reflectivity. Each image of the transient reflectivity ΔR/R at different time delays is a display of the 2D acousto-optic response. The transient reflectivity change reaches about −4×10−3 at the blue center part of the images. The fact that the center blue part on the images reaches two pseudo-maxima at τ = 63 ps and 72.7 ps is inherent to the acousto-optic detection of an unipolar acoustic pulse at a free surface. The orange edge part which changes the transient reflectivity by about 2×10−3 and appears at different time delays compared to the blue center part is the signature of the nonlinear acoustic propagation of the acoustic pulse trough gold.

The foremost observation in nonlinear laser acoustics (high-power laser excitation of weak to strong shock waves [1

1. T. Pezeril, G. Saini, D. Veysset, S. Kooi, P. Fidkowski, R. Radovitzky, and K. A. Nelson, “Direct visualization of laser-driven focusing shock waves,” Phys. Rev. Lett. 106(4), 214503 (2011). [CrossRef] [PubMed]

, 22

22. V. Temnov, C. Klieber, K. A. Nelson, T. Thomay, V. Knittel, A. Leitenstorfer, D. Makarov, M. Albrecht, and R. Bratschitsch, “Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons,” Nat. Commun. 4(6), 1468 (2013). [CrossRef] [PubMed]

, 29

29. P. J. S. van Capel and J. I. Dijkhuis, “Optical generation and detection of shock waves in sapphire at room temperature,” Appl. Phys. Lett. 88(3), 151910 (2006). [CrossRef]

, 30

30. A. Bojahr, M. Herzog, D. Schick, I. Vrejoiu, and M. Bargheer, “Calibrated real-time detection of nonlinearly propagating strain waves,” Phys. Rev. B 86(5), 144306 (2012). [CrossRef]

] or solitons [31

31. H. Y. Hao and H. J. Maris, “Experiments with acoustic solitons in crystalline solids,” Phys. Rev. B 64(7), 064302 (2001). [CrossRef]

33

33. P. J. S. van Capel and J. I. Dijkhuis, “Time-resolved interferometric detection of ultrashort strain solitons in sapphire,” Phys. Rev. B 81(9), 144106 (2010). [CrossRef]

]) is the increase in sound velocity (over the speed of sound of the material) of large pressure acoustic pulses. As a matter of fact, any experimental evidence of the acoustic velocity being dependent on the acoustic pressure implies the involvement of nonlinear acoustics. The sequence of reflectivity images of Fig. 2, in particular the orange edge portion whose maximum has a time offset as compared to the blue center part (compare the images at τ = 72.7 ps and 83 ps in Fig. 2) is a direct demonstration of the nonlinear propagation of the inhomogeneous acoustic pulse. Since the laser pump is focused as an inhomogeneous 2D gaussian profile, see Fig. 1(a), the non-uniform amplitude of the laser pump will give rise to an inhomogeneous acoustic pulse that does not travel at a constant speed. As a consequence, the acoustic speed will be non-uniform along the in-plane position of the acoustic pulse. This is the reason for the center blue portion of the acoustic pulse with higher acoustic pressure arriving before the orange edge portion with lower acoustic pressure. A second step of image analysis provides deeper insight into the observation of the governing nonlinear acoustic phenomena. In this step, each image of the sequence has been processed with a predefined image mask - adapted to the 2D Gaussian excitation profile, with four plus one different areas in order to isolate five different subimages. A selected raw image and the adapted mask are shown in Figs. 3(a) and 3(b). The mask has a central part, the first area with a disk-like shape centered at the in-plane position of the maximum transient reflectivity signal, and corresponds to the maximum in pump light intensity. Finally, the last region, Area 5, serves as a reference area with negligible pump induced transient reflectivity signal to quantify the measurement noise. After applying the mask, the mean values of each of the five resulting subimages are calculated. From all the images constituting the sequence, we obtain the picosecond time evolution of the mean values for each of the 4 areas - as displayed in Figs. 3(c) and 3(d). While Fig. 3(c) shows the extracted mean values of Areas 1 through 4, Fig. 3(d) shows the same results after subtractions of the mean value of the reference area, Area 5, which diminishes the noise level further. Comparison of the results of Area 4 shown in Figs. 3(c) with 3(d) demonstrates that the subtraction of the reference area removes noise by about a factor of 3 – a substantial improvement of data quality. More quantitatively, the STD value of Area 4 decreases from 8.9×10−5 to 3.4×10−5 when the reference Area is subtracted. In case of gold and a probe wavelength of 400 nm [28

28. K. J. Manke, A. A. Maznev, C. Klieber, V. Shalagatskyi, V. V. Temnov, D. Makarov, S.-H. Baek, C.-B. Eom, and K. A. Nelson, “Measurement of shorter-than-skin-depth acoustic pulses in a metal film via transient reflectivity,” Appl. Phys. Lett. 103(4), 173104 (2013). [CrossRef]

], the time derivative of the transient reflectivity signal approximates very well the acoustic strain profile η in Eq. (2). As a final step, we perform the time derivation of the reflectivity signals displayed in Fig. 3(d), which yields the approximate acoustic pulse profiles for each of the four different areas. The results of this procedure in Fig. 3(e) highlight that the acoustic pulse arrival is different for the 4 different areas with different acoustic pressures. From the acoustic pulse with higher pressure (Area 1) arriving before the acoustic pulse with lower pressure (Area 4), we conclude the nonlinear acoustic propagation through gold. Between Area 1 and Area 4, we measure a time jitter of about 1.6 ps in arrival time of the acoustic pulse, consistent with what has been measured with femtosecond surface plasmon interferometry [22

22. V. Temnov, C. Klieber, K. A. Nelson, T. Thomay, V. Knittel, A. Leitenstorfer, D. Makarov, M. Albrecht, and R. Bratschitsch, “Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons,” Nat. Commun. 4(6), 1468 (2013). [CrossRef] [PubMed]

]. This time jitter only depends on the third order elastic parameter of gold and on the peak amplitude of the generated acoustic pulse. In case of gold, since this nonlinear elastic coefficient is already known [34

34. Y. Hiki and A. V. Granato, “Anharmonicity in noble metals; higher order elastic constants,” Phys. Rev. 144, 411–419 (1966). [CrossRef]

], our results displayed in Fig. 3, directly scaled in absolute units, can be used to estimate the absolute value of the photoelastic coefficients in the sensitivity function s(z) of Eq. (2). From the comparison of the measured intensity-dependence of the time jitter with the solutions of the nonlinear Korteveg-de Vries (KdV) theory [22

22. V. Temnov, C. Klieber, K. A. Nelson, T. Thomay, V. Knittel, A. Leitenstorfer, D. Makarov, M. Albrecht, and R. Bratschitsch, “Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons,” Nat. Commun. 4(6), 1468 (2013). [CrossRef] [PubMed]

, 31

31. H. Y. Hao and H. J. Maris, “Experiments with acoustic solitons in crystalline solids,” Phys. Rev. B 64(7), 064302 (2001). [CrossRef]

], we obtain an estimate of the photoelastic coefficients in gold at 400 nm probe wavelength, dn/dη = 2.0 ± 0.7 and dk/dη = 1.0 ± 0.3. Vice versa when a material is studied with unknown nonlinear elastic coefficient, the analysis of the time jitter and the nonlinear reshaping of ultrashort acoustic pulses can be exploited to extract the values of elastic nonlinearities.

Fig. 3 a) and b) After image processing, every transient reflectivity image at each time delay has been numerically split in 4 different areas and a reference area defined by an image mask. These five areas of the image mask include Area 1 which comprises the center of the transient reflectivity maximum, Areas 2 through 4 as concentric areas around the center and the Reference Area with negligible pump induced transient reflectivity signal which is used as a noise reference image. c) Mean transient reflectivity signal of each of the four concentric areas. d) The signal-to-noise level is increased by a factor of 3 when the noise reference Area is used in the image processing. e) The smoothed time derivatives of the signals shown in d) reveal different arrival times of the acoustic pulse at the front gold surface for different areas corresponding to different laser pump power inputs. We observe a 1.6 ps time difference between the areas of maximum (Area 1) and minimum (Area 4) pump fluence which is in close agreement with the calculated estimates of the nonlinear acoustic propagation in gold.

4. Conclusion

Through this paper we introduced an ultrafast pump-probe experiment based on lock-in acquisition of images. The technique enables direct 2D visualization of femtosecond laser induced phenomena. To illustrate the high-sensitivity, low-noise performance of the developed setup, we present the direct visualization of the nonlinear propagation and reshaping of an ultrashort acoustic pulse in gold. Potentially, this experimental technique could lead to a simple and routine measurement of nonlinear elastic parameters of many materials. To facilitate the detection of even smaller features in time resolved images it could be possible to further increase the image resolution close to the diffraction limit. The detection sensitivity could be improved further with a new type of low noise CMOS sensors with a frame rate of ∼ 800 Hz at 256×512 pixels resolution (Hamamatsu OrcaFlash), and by using different detection techniques [35

35. Y. Li, Q. Miao, A. V. Nurmikko, and H. J. Marisa, “Picosecond ultrasonic measurements using an optical cavity,” J. Appl. Phys. 105(8), 083516 (2009). [CrossRef]

37

37. D. H. Feng, X. Q. Pan, X. Li, T. Q. Jia, and Z. R. Sun, “Coherent acoustic phonon generation and detection by femtosecond laser pulses in ZnTe single crystals,” J. Appl. Phys. 114(9), 093513 (2013). [CrossRef]

]. Beyond that, we envision to use this new technique for imaging longitudinal or transverse ultrasonic echoes in biological or liquid samples [38

38. T. Pezeril, V. Gusev, D. Mounier, and P. Ruello, “Surface motion induced by laser action on opaque anisotropic crystals,” J. Phys. D Appl. Phys. 38, 1421–1428 (2005). [CrossRef]

42

42. M. Ducousso, O. E.-F. Zouani, C. Chanseau, C. Chollet, C. Rossignol, B. Audoin, and M.-C. Durrieu, “Evaluation of mechanical properties of fixed bone cells with sub-micrometer thickness by picosecond ultrasonics,” Eur. Phys. J. Appl. Phys. 61(10), 11201 (2013). [CrossRef]

] or to adapt the experiment for Magneto-optical Kerr measurements in order to image magnetic domains subjected to ultrashort acoustic pulses [43

43. O. Kovalenko, T. Pezeril, and V. Temnov, “New concept for magnetization switching by ultrafast acoustic pulses,” Phys. Rev. Lett. 110(5), 266602 (2013). [CrossRef] [PubMed]

]. The latest results can be found online [44].

Acknowledgments

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T. Pezeril, G. Saini, D. Veysset, S. Kooi, P. Fidkowski, R. Radovitzky, and K. A. Nelson, “Direct visualization of laser-driven focusing shock waves,” Phys. Rev. Lett. 106(4), 214503 (2011). [CrossRef] [PubMed]

2.

C. A. Werley, S. M. Teo, B. K. Ofori-Okai, P. Sivarajah, and K. A. Nelson, “High-resolution, low-noise imaging in THz polaritonics,” IEEE Trans. Terahertz Sci. Technol. 3, 239–247 (2013). [CrossRef]

3.

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O. B. Wright and K. Kawashima, “Coherent phonon detection from ultrafast surface vibrations,” Phys. Rev. Lett. 69, 1668–1671 (1992). [CrossRef] [PubMed]

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T. Saito, O. Matsuda, and O. B. Wright, “Picosecond acoustic phonon pulse generation in nickel and chromium,” Phys. Rev. B 67(7), 205421 (2003). [CrossRef]

6.

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12.

B. C. Daly, N. C. R. Holme, T. Buma, C. Branciard, T. B. Norris, D. M. Tennant, J. A. Taylor, J. E. Bower, and S. Pau, “Imaging nanostructures with coherent phonon pulses,” Appl. Phys. Lett. 84(25), 5180–5182 (2004). [CrossRef]

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14.

A. Amziane, L. Belliard, F. Decremps, and B. Perrin, “Ultrafast acoustic resonance spectroscopy of gold nanostructures: Towards a generation of tunable transverse waves,” Phys. Rev. B 83(7), 014102 (2011). [CrossRef]

15.

S. Bourquin, R. P. Prasankumar, F. X. Kartner, J. G. Fujimoto, T. Lasser, and R. P. Salathe, “High-speed femtosecond pump-probe spectroscopy with a smart pixel detector array,” Opt. Lett. 28(3), 1588–1590 (2003). [CrossRef] [PubMed]

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E. Pontecorvo, M. Ortolani, D. Polli, M. Ferretti, G. Ruocco, G. Cerullo, and T. Scopigno, “Visualizing coherent phonon propagation in the 100 GHz range: A broadband picosecond acoustics approach,” Appl. Phys. Lett. 98(3), 011901 (2011). [CrossRef]

19.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, “Ultrafast time-domain spectroscopy based on high-speed asynchronous optical sampling,” Rev. Sci. Instrum. 78, 035107 (2007). [CrossRef] [PubMed]

20.

S. Dilhaire, G. Pernot, G. Calbris, J. M. Rampnoux, and S. Grauby, “Heterodyne picosecond thermoreflectance applied to nanoscale thermal metrology,” J. Appl. Phys. 110(13), 114314 (2011). [CrossRef]

21.

E. Peronne, E. Charron, S. Vincent, S. Sauvage, A. Lemaitre, B. Perrin, and B. Jusserand, “Two-color femtosecond strobe lighting of coherent acoustic phonons emitted by quantum dots,” Appl. Phys. Lett. 102(4), 043107 (2013). [CrossRef]

22.

V. Temnov, C. Klieber, K. A. Nelson, T. Thomay, V. Knittel, A. Leitenstorfer, D. Makarov, M. Albrecht, and R. Bratschitsch, “Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons,” Nat. Commun. 4(6), 1468 (2013). [CrossRef] [PubMed]

23.

T. Pezeril, F. Leon, D. Chateigner, S. Kooi, and K. A. Nelson, “Picosecond photoexcitation of acoustic waves in locally canted gold films,” Appl. Phys. Lett. 92(3), 061908 (2008). [CrossRef]

24.

P.-A. Mante, A. Devos, and A. Le Louarn, “Generation of terahertz acoustic waves in semiconductor quantum dots using femtosecond laser pulses,” Phys. Rev. B 81(11), 113305 (2010). [CrossRef]

25.

B. Perrin, B. Bonello, J. C. Jeannet, and E. Romatet, “Interferometric detection of hypersound waves in modulated structures, ” Prog. Nat. Sci. Suppl. 6, S444 (1996).

26.

D. H. Hurley and O. B. Wright, “Detection of ultrafast phenomena by use of a modified Sagnac interferometer,” Opt. Lett. 24, 1305–1307 (1999). [CrossRef]

27.

O. Matsuda, M. Tomoda, and T. Tachizaki, “Ultrafast ellipsometric interferometry for direct detection of coherent phonon strain pulse profiles,” J. Opt. Soc. Am. B 30, 1911–1921 (2013). [CrossRef]

28.

K. J. Manke, A. A. Maznev, C. Klieber, V. Shalagatskyi, V. V. Temnov, D. Makarov, S.-H. Baek, C.-B. Eom, and K. A. Nelson, “Measurement of shorter-than-skin-depth acoustic pulses in a metal film via transient reflectivity,” Appl. Phys. Lett. 103(4), 173104 (2013). [CrossRef]

29.

P. J. S. van Capel and J. I. Dijkhuis, “Optical generation and detection of shock waves in sapphire at room temperature,” Appl. Phys. Lett. 88(3), 151910 (2006). [CrossRef]

30.

A. Bojahr, M. Herzog, D. Schick, I. Vrejoiu, and M. Bargheer, “Calibrated real-time detection of nonlinearly propagating strain waves,” Phys. Rev. B 86(5), 144306 (2012). [CrossRef]

31.

H. Y. Hao and H. J. Maris, “Experiments with acoustic solitons in crystalline solids,” Phys. Rev. B 64(7), 064302 (2001). [CrossRef]

32.

E. Peronne and B. Perrin, “Generation and detection of acoustic solitons in crystalline slabs by laser ultrasonics,” Ultrasonics 44, 1203–1207 (2006). [CrossRef]

33.

P. J. S. van Capel and J. I. Dijkhuis, “Time-resolved interferometric detection of ultrashort strain solitons in sapphire,” Phys. Rev. B 81(9), 144106 (2010). [CrossRef]

34.

Y. Hiki and A. V. Granato, “Anharmonicity in noble metals; higher order elastic constants,” Phys. Rev. 144, 411–419 (1966). [CrossRef]

35.

Y. Li, Q. Miao, A. V. Nurmikko, and H. J. Marisa, “Picosecond ultrasonic measurements using an optical cavity,” J. Appl. Phys. 105(8), 083516 (2009). [CrossRef]

36.

C.-K. Min, D. G. Cahill, and S. Granick, “Time-resolved ellipsometry for studies of heat transfer at liquid/solid and gas/solid interfaces,” Rev. Sci. Instrum. 81(7), 074902 (2010). [CrossRef] [PubMed]

37.

D. H. Feng, X. Q. Pan, X. Li, T. Q. Jia, and Z. R. Sun, “Coherent acoustic phonon generation and detection by femtosecond laser pulses in ZnTe single crystals,” J. Appl. Phys. 114(9), 093513 (2013). [CrossRef]

38.

T. Pezeril, V. Gusev, D. Mounier, and P. Ruello, “Surface motion induced by laser action on opaque anisotropic crystals,” J. Phys. D Appl. Phys. 38, 1421–1428 (2005). [CrossRef]

39.

T. Pezeril, P. Ruello, N. Chigarev, S. Gougeon, D. Mounier, J.-M. Breteau, P. Picart, and V. Gusev, “Generation and detection of plane coherent shear picosecond acoustic pulses by lasers: Experiment and theory,” Phys. Rev. B 75(19), 174307 (2007). [CrossRef]

40.

T. Pezeril, C. Klieber, S. Andrieu, and K. A. Nelson, “Optical generation of gigahertz-frequency shear acoustic waves in liquid glycerol,” Phys. Rev. Lett. 102(4), 107402 (2009). [CrossRef] [PubMed]

41.

C. Klieber, T. Pezeril, S. Andrieu, and K. A. Nelson, “Optical generation and detection of gigahertz-frequency longitudinal and shear acoustic waves in liquids: theory and experiment,” J. Appl. Phys. 112(11), 013502 (2012). [CrossRef]

42.

M. Ducousso, O. E.-F. Zouani, C. Chanseau, C. Chollet, C. Rossignol, B. Audoin, and M.-C. Durrieu, “Evaluation of mechanical properties of fixed bone cells with sub-micrometer thickness by picosecond ultrasonics,” Eur. Phys. J. Appl. Phys. 61(10), 11201 (2013). [CrossRef]

43.

O. Kovalenko, T. Pezeril, and V. Temnov, “New concept for magnetization switching by ultrafast acoustic pulses,” Phys. Rev. Lett. 110(5), 266602 (2013). [CrossRef] [PubMed]

44.

http://perso.univ-lemans.fr/~tpezeril/crbst_5.html

OCIS Codes
(110.7170) Imaging systems : Ultrasound
(320.0320) Ultrafast optics : Ultrafast optics
(100.0118) Image processing : Imaging ultrafast phenomena

ToC Category:
Imaging Systems

History
Original Manuscript: November 29, 2013
Revised Manuscript: January 10, 2014
Manuscript Accepted: January 11, 2014
Published: February 20, 2014

Virtual Issues
Vol. 9, Iss. 4 Virtual Journal for Biomedical Optics

Citation
Thomas Pezeril, Christoph Klieber, Viktor Shalagatskyi, Gwenaelle Vaudel, Vasily Temnov, Oliver G. Schmidt, and Denys Makarov, "Femtosecond imaging of nonlinear acoustics in gold," Opt. Express 22, 4590-4598 (2014)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-22-4-4590


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References

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  14. A. Amziane, L. Belliard, F. Decremps, B. Perrin, “Ultrafast acoustic resonance spectroscopy of gold nanostructures: Towards a generation of tunable transverse waves,” Phys. Rev. B 83(7), 014102 (2011). [CrossRef]
  15. S. Bourquin, R. P. Prasankumar, F. X. Kartner, J. G. Fujimoto, T. Lasser, R. P. Salathe, “High-speed femtosecond pump-probe spectroscopy with a smart pixel detector array,” Opt. Lett. 28(3), 1588–1590 (2003). [CrossRef] [PubMed]
  16. R. J. Smith, M. G. Somekh, S. D. Sharples, M. C. Pitter, I. Harrison, C. Rossignol, “Parallel detection of low modulation depth signals: application to picosecond ultrasonics,” Meas. Sci. Technol. 19(8), 055301 (2008). [CrossRef]
  17. R. J. Smith, R. A. Light, S. D. Sharples, N. S. Johnston, M. C. Pitter, M. G. Somekh, “Multichannel, time-resolved picosecond laser ultrasound imaging and spectroscopy with custom complementary metal-oxide-semiconductor detector,” Rev. Sci. Instrum. 81, 024901 (2010). [CrossRef] [PubMed]
  18. E. Pontecorvo, M. Ortolani, D. Polli, M. Ferretti, G. Ruocco, G. Cerullo, T. Scopigno, “Visualizing coherent phonon propagation in the 100 GHz range: A broadband picosecond acoustics approach,” Appl. Phys. Lett. 98(3), 011901 (2011). [CrossRef]
  19. A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, T. Dekorsy, “Ultrafast time-domain spectroscopy based on high-speed asynchronous optical sampling,” Rev. Sci. Instrum. 78, 035107 (2007). [CrossRef] [PubMed]
  20. S. Dilhaire, G. Pernot, G. Calbris, J. M. Rampnoux, S. Grauby, “Heterodyne picosecond thermoreflectance applied to nanoscale thermal metrology,” J. Appl. Phys. 110(13), 114314 (2011). [CrossRef]
  21. E. Peronne, E. Charron, S. Vincent, S. Sauvage, A. Lemaitre, B. Perrin, B. Jusserand, “Two-color femtosecond strobe lighting of coherent acoustic phonons emitted by quantum dots,” Appl. Phys. Lett. 102(4), 043107 (2013). [CrossRef]
  22. V. Temnov, C. Klieber, K. A. Nelson, T. Thomay, V. Knittel, A. Leitenstorfer, D. Makarov, M. Albrecht, R. Bratschitsch, “Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons,” Nat. Commun. 4(6), 1468 (2013). [CrossRef] [PubMed]
  23. T. Pezeril, F. Leon, D. Chateigner, S. Kooi, K. A. Nelson, “Picosecond photoexcitation of acoustic waves in locally canted gold films,” Appl. Phys. Lett. 92(3), 061908 (2008). [CrossRef]
  24. P.-A. Mante, A. Devos, A. Le Louarn, “Generation of terahertz acoustic waves in semiconductor quantum dots using femtosecond laser pulses,” Phys. Rev. B 81(11), 113305 (2010). [CrossRef]
  25. B. Perrin, B. Bonello, J. C. Jeannet, E. Romatet, “Interferometric detection of hypersound waves in modulated structures, ” Prog. Nat. Sci. Suppl. 6, S444 (1996).
  26. D. H. Hurley, O. B. Wright, “Detection of ultrafast phenomena by use of a modified Sagnac interferometer,” Opt. Lett. 24, 1305–1307 (1999). [CrossRef]
  27. O. Matsuda, M. Tomoda, T. Tachizaki, “Ultrafast ellipsometric interferometry for direct detection of coherent phonon strain pulse profiles,” J. Opt. Soc. Am. B 30, 1911–1921 (2013). [CrossRef]
  28. K. J. Manke, A. A. Maznev, C. Klieber, V. Shalagatskyi, V. V. Temnov, D. Makarov, S.-H. Baek, C.-B. Eom, K. A. Nelson, “Measurement of shorter-than-skin-depth acoustic pulses in a metal film via transient reflectivity,” Appl. Phys. Lett. 103(4), 173104 (2013). [CrossRef]
  29. P. J. S. van Capel, J. I. Dijkhuis, “Optical generation and detection of shock waves in sapphire at room temperature,” Appl. Phys. Lett. 88(3), 151910 (2006). [CrossRef]
  30. A. Bojahr, M. Herzog, D. Schick, I. Vrejoiu, M. Bargheer, “Calibrated real-time detection of nonlinearly propagating strain waves,” Phys. Rev. B 86(5), 144306 (2012). [CrossRef]
  31. H. Y. Hao, H. J. Maris, “Experiments with acoustic solitons in crystalline solids,” Phys. Rev. B 64(7), 064302 (2001). [CrossRef]
  32. E. Peronne, B. Perrin, “Generation and detection of acoustic solitons in crystalline slabs by laser ultrasonics,” Ultrasonics 44, 1203–1207 (2006). [CrossRef]
  33. P. J. S. van Capel, J. I. Dijkhuis, “Time-resolved interferometric detection of ultrashort strain solitons in sapphire,” Phys. Rev. B 81(9), 144106 (2010). [CrossRef]
  34. Y. Hiki, A. V. Granato, “Anharmonicity in noble metals; higher order elastic constants,” Phys. Rev. 144, 411–419 (1966). [CrossRef]
  35. Y. Li, Q. Miao, A. V. Nurmikko, H. J. Marisa, “Picosecond ultrasonic measurements using an optical cavity,” J. Appl. Phys. 105(8), 083516 (2009). [CrossRef]
  36. C.-K. Min, D. G. Cahill, S. Granick, “Time-resolved ellipsometry for studies of heat transfer at liquid/solid and gas/solid interfaces,” Rev. Sci. Instrum. 81(7), 074902 (2010). [CrossRef] [PubMed]
  37. D. H. Feng, X. Q. Pan, X. Li, T. Q. Jia, Z. R. Sun, “Coherent acoustic phonon generation and detection by femtosecond laser pulses in ZnTe single crystals,” J. Appl. Phys. 114(9), 093513 (2013). [CrossRef]
  38. T. Pezeril, V. Gusev, D. Mounier, P. Ruello, “Surface motion induced by laser action on opaque anisotropic crystals,” J. Phys. D Appl. Phys. 38, 1421–1428 (2005). [CrossRef]
  39. T. Pezeril, P. Ruello, N. Chigarev, S. Gougeon, D. Mounier, J.-M. Breteau, P. Picart, V. Gusev, “Generation and detection of plane coherent shear picosecond acoustic pulses by lasers: Experiment and theory,” Phys. Rev. B 75(19), 174307 (2007). [CrossRef]
  40. T. Pezeril, C. Klieber, S. Andrieu, K. A. Nelson, “Optical generation of gigahertz-frequency shear acoustic waves in liquid glycerol,” Phys. Rev. Lett. 102(4), 107402 (2009). [CrossRef] [PubMed]
  41. C. Klieber, T. Pezeril, S. Andrieu, K. A. Nelson, “Optical generation and detection of gigahertz-frequency longitudinal and shear acoustic waves in liquids: theory and experiment,” J. Appl. Phys. 112(11), 013502 (2012). [CrossRef]
  42. M. Ducousso, O. E.-F. Zouani, C. Chanseau, C. Chollet, C. Rossignol, B. Audoin, M.-C. Durrieu, “Evaluation of mechanical properties of fixed bone cells with sub-micrometer thickness by picosecond ultrasonics,” Eur. Phys. J. Appl. Phys. 61(10), 11201 (2013). [CrossRef]
  43. O. Kovalenko, T. Pezeril, V. Temnov, “New concept for magnetization switching by ultrafast acoustic pulses,” Phys. Rev. Lett. 110(5), 266602 (2013). [CrossRef] [PubMed]
  44. http://perso.univ-lemans.fr/~tpezeril/crbst_5.html

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