OSA's Digital Library

Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 14 — Jul. 15, 2013
  • pp: 17221–17227
« Show journal navigation

Plasmonic photoconductive detectors for enhanced terahertz detection sensitivity

Ning Wang, Mohammad R. Hashemi, and Mona Jarrahi  »View Author Affiliations


Optics Express, Vol. 21, Issue 14, pp. 17221-17227 (2013)
http://dx.doi.org/10.1364/OE.21.017221


View Full Text Article

Acrobat PDF (2544 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

A photoconductive terahertz detector based on plasmonic contact electrodes is presented. The use of plasmonic electrodes mitigates the inherent tradeoff between high quantum efficiency and ultrafast operation of the employed photoconductor, enabling significantly higher detection sensitivities compared to conventional photoconductive terahertz detectors. Prototypes of comparable photoconductive detectors with and without plasmonic contact electrode gratings were fabricated and characterized in a time-domain terahertz spectroscopy setup under the same operation conditions. The experimental results show that the plasmonic photoconductive detector offers more than 30 times higher terahertz detection sensitivities compared to the comparable conventional photoconductive detector without plasmonic contact electrodes over 0.1-1.5 THz frequency band.

© 2013 OSA

1. Introduction

Photoconductive terahertz detectors are extensively used in time-domain and frequency-domain terahertz imaging and spectroscopy systems [1

1. P. R. Smith, D. H. Auston, and M. C. Nuss, “Subpicosecond photoconducting dipole antennas,” IEEE J. Quantum Electron. 24(2), 255–260 (1988). [CrossRef]

14

14. B. Heshmat, H. Pahlevaninezhad, Y. Pang, M. Masnadi-Shirazi, R. Burton Lewis, T. Tiedje, R. Gordon, and T. E. Darcie, “Nanoplasmonic Terahertz Photoconductive Switch on GaAs,” Nano Lett. 12(12), 6255–6259 (2012). [CrossRef] [PubMed]

] for various chemical sensing, product quality control, medical imaging, bio-sensing, pharmaceutical, and security screening applications [15

15. M. Tani, M. Herrmann, and K. Sakai, “Generation and detection of terahertz pulsed radiation with photoconductive antennas and its application to imaging,” Meas. Sci. Technol. 13(11), 1739–1745 (2002). [CrossRef]

22

22. M. C. Kemp, P. F. Taday, B. E. Cole, J. A. Cluff, A. J. Fitzgerald, and W. R. Tribe, “Security applications of terahertz technology,” Proc. SPIE 5070, 44–52 (2003). [CrossRef]

]. A photoconductive terahertz detector consists of an ultrafast photoconductor pumped by a pulsed [23

23. S. Kono, M. Tani, and K. Sakai, “Coherent detection of mid-infrared radiation up to 60 THz with an LT-GaAs photoconductive antenna,” IEE Proc. Optoelectronics 149, 105- 109 (2002). [CrossRef]

] or heterodyned [24

24. S. Verghese, K. A. McIntosh, S. Calawa, W. F. Dinatale, E. K. Duerr, and K. A. Molvar, “Generation and detection of coherent terahertz waves using two Photomixers,” Appl. Phys. Lett. 73(26), 3824–3826 (1998). [CrossRef]

] optical pump. The ultrafast photoconductor is integrated with a terahertz antenna, which receives incident terahertz radiation and induces a terahertz electric field across the photoconductor contact electrodes. Terahertz detection is the result of the induced terahertz field drifting photo-generated carrier inside the photoconductor active region, generating an output photocurrent proportional to the intensity of the incident terahertz field. The inherent tradeoff between high quantum efficiency and ultrafast operation of conventional photoconductors has severely limited the detection sensitivity of conventional photoconductive terahertz detectors. To address the quantum efficiency limitation of ultrafast photoconductors, we present a new type of photoconductor that enables high quantum efficiency and ultrafast operation, simultaneously. This new type of photoconductor incorporates plasmonic contact electrodes to manipulate the distribution of the photo-generated carriers inside the photoconductor active region and enhance carrier concentration in close proximity with photoconductor contact electrodes. By reducing the carrier transport path to the photoconductor contact electrodes, the number of the drifted carriers to the photoconductor contact electrodes within a sub-picosecond time-scale is increased significantly, offering higher detection sensitivities for the incident terahertz radiation. In this work, we experimentally demonstrate that incorporating plasmonic gratings in the contact electrodes of a conventional photoconductive terahertz detector offers a 30 fold enhancement in the terahertz detection sensitivity over 0.1-1.5 THz frequency band.

2. Photoconductive detector design and operation

To evaluate the impact of plasmonic contact electrodes in enhancing the detection sensitivity of photoconductive terahertz detectors, we have characterized the performance of a conventional photoconductive terahertz detector before and after incorporating plasmonic contact electrodes.

Figure 1(a)
Fig. 1 Schematic view and operation concept of comparable conventional (a) and plasmonic (b) photoconductive terahertz detectors, used for evaluating the impact of plasmonic contact electrodes on the photoconductive terahertz detector performance.
shows the schematic diagram and operation concept of the conventional photoconductive terahertz detector used in this study. The detector consists of an ultrafast photoconductor with 30 μm contact electrode width and 10 μm contact electrode spacing. The ultrafast photoconductor is integrated with a 60 μm long bowtie antenna with maximum and minimum widths of 100 μm and 30 μm, respectively, on a low-temperature grown (LT) GaAs substrate. The detector is mounted on a silicon lens, which helps focusing the incident terahertz radiation onto the device. When a terahertz beam is incident on the detector, a terahertz electric field, ETHz, is induced across photoconductor contact electrodes, which drifts the photocarriers generated upon incidence of an optical pump. This generates an output photocurrent, Iout, which follows the envelope of the received terahertz field. For high sensitivity terahertz detection, the optical pump is focused onto the photoconductive gap asymmetrically close to one of the photoconductor contact electrodes [25

25. P. C. Upadhya, W. Fan, A. Burnett, J. Cunningham, A. G. Davies, E. H. Linfield, J. Lloyd-Hughes, E. Castro-Camus, M. B. Johnston, and H. Beere, “Excitation-density-dependent generation of broadband terahertz radiation in an asymmetrically excited photoconductive antenna,” Opt. Lett. 32(16), 2297–2299 (2007). [CrossRef] [PubMed]

27

27. C. W. Berry and M. Jarrahi, “Principles of impedance matching in photoconductive antennas,” J. Infrared Milli. Terahz. Waves 33(12), 1182–1189 (2012). [CrossRef]

]. Asymmetric optical excitation enhances the photocarrier concentration in close proximity to the photoconductor contact electrode with the highest induced terahertz electric field levels and, thus, the output photocurrent. However, due to the relatively low drift velocity of carriers in the photo-absorbing substrate [28

28. J. Požela and A. Reklaitis, “Electron transport properties in GaAs at high electric fields,” Solid-State Electron. 23(9), 927–933 (1980). [CrossRef]

], a small portion of the photocarriers can reach the photoconductor contact electrodes within a sub-picosecond time-scale, limiting the terahertz detection sensitivity of the conventional photoconductive terahertz detector.

Figure 1(b) shows the schematic diagram and operation concept of the plasmonic photoconductive terahertz detector, designed to increase the detection sensitivity of the conventional photoconductive terahertz detector, by incorporating plasmonic gratings in the photoconductor contact electrodes. The plasmonic contact electrode gratings (200 nm pitch, 100 nm spacing, and 50 nm height Au gratings in this case) are designed to allow excitation of surface plasmon waves along the nanoscale gratings in response to a y-polarized incident optical pump at a 800 nm wavelength [29

29. C. W. Berry and M. Jarrahi, “Plasmonically-enhanced localization of light into photoconductive antennas,” Proc. Conf. Lasers and Electro-Optics, CFI2 (2010). [CrossRef]

32

32. C. W. Berry, J. Moore, and M. Jarrahi, “Design of Reconfigurable Metallic Slits for Terahertz Beam Modulation,” Opt. Express 19(2), 1236–1245 (2011). [CrossRef] [PubMed]

]. Excitation of the surface plasmon waves enables transmission of more than 70% of the optical pump into the nanoscale semiconductor active regions between the plasmonic contact electrode gratings, as illustrated in Fig. 2(a)
Fig. 2 (a) Optical power transmission through the designed plasmonic contact electrodes with 200 nm pitch, 100 nm spacing, 50 nm height Au gratings, and 150 nm SiO2 passivation layer into the active region of the plasmonic photoconductive detector (blue curve) and its comparison with optical power transmission into the active region of the conventional photoconductive detector (red curve). A multi-physics finite element solver (COMSOL) is used to estimate the optical power transmission into the active region of plasmonic and conventional photoconductive detectors. No passivation layer is used for the conventional photoconductive detector to achieve the same optical power transmission for the conventional and plasmonic designs at 800 nm pump wavelength. This allows a fair evaluation of the impact of the plasmonic contact electrodes. (b) Absorption of a 800 nm optical pump (y-polarized) inside the GaAs substrate at the plasmonic contact electrodes cross section, indicating optical absorption enhancement in close proximity with the plasmonic contact electrodes. The COMSOL multi-physics finite element solver is used to estimate the optical pump absorption distribution inside the GaAs substrate.
. Moreover, since the excited surface plasmon waves are tightly confined at the metal-semiconductor interface, the optical pump intensity is further enhanced in close proximity to the Au contact electrodes, as illustrated in Fig. 2(b). Therefore, the average transport path of the photo-generated carriers to the photoconductor contact electrodes is significantly reduced compared to case of the conventional photoconductive terahertz detector, leading to a significant increase in the number of the drifted carriers to the photoconductor contact electrodes in a sub-picosecond time-scale. Therefore, while the output photocurrents of the plasmonic and conventional photoconductive detectors both follow the envelope of the received terahertz field, significantly larger output photocurrents will be offered by the plasmonic photoconductive detector under the same incident terahertz intensities.

An additional advantage of the presented plasmonic photoconductive detector in comparison with conventional photoconductive detectors and previously demonstrated plasmonic photoconductive detectors [13

13. S. Liu, X. Shou, and A. Nahata, “Coherent Detection of Multiband Terahertz Radiation Using a Surface Plasmon-Polariton Based Photoconductive Antenna,” IEEE Trans. Terahertz Sci. Technol. 1(2), 412–415 (2011). [CrossRef]

, 14

14. B. Heshmat, H. Pahlevaninezhad, Y. Pang, M. Masnadi-Shirazi, R. Burton Lewis, T. Tiedje, R. Gordon, and T. E. Darcie, “Nanoplasmonic Terahertz Photoconductive Switch on GaAs,” Nano Lett. 12(12), 6255–6259 (2012). [CrossRef] [PubMed]

] is that device active area can be increased by extending the length of the plasmonic contact electrodes, without a considerable increase in photoconductor capacitive parasitics. Increasing the photoconductor active area enables mitigating the carrier screening effect and optical breakdown at high optical pump power levels [33

33. M. Beck, H. Schäfer, G. Klatt, J. Demsar, S. Winnerl, M. Helm, and T. Dekorsy, “Impulsive terahertz radiation with high electric fields from an amplifier-driven large-area photoconductive antenna,” Opt. Express 18(9), 9251–9257 (2010). [CrossRef] [PubMed]

37

37. A. Dreyhaupt, S. Winnerl, T. Dekorsy, and M. Helm, “High-intensity terahertz radiation from a microstructured large-area photoconductor,” Appl. Phys. Lett. 86(12), 121114 (2005). [CrossRef]

]. Therefore, this design flexibility is helpful to enhance the highest achievable detector responsivity and sensitivity by increasing the optical pump power.

3. Experimental results and discussion

Prototypes of comparable conventional and plasmonic photoconductive terahertz detectors (Fig. 1) were fabricated on the same LT-GaAs substrate. Using electron beam lithography, the plasmonic gratings were first patterned, followed by deposition of Ti/Au (50/450 Å) and liftoff. A 1500 Å SiO2 passivation layer was then deposited using plasma enhanced chemical vapor deposition. Using optical photolithography and dry plasma etching, contact vias were etched through the SiO2 layer. Finally, the antennas, bias lines, and vias were patterned using optical lithography, followed by Ti/Au (100/4000 Å) deposition and liftoff. Figure 3
Fig. 3 Microscope image of the fabricated conventional and plasmonic photoconductive detectors, as well as the SEM image of the plasmonic contact electrode gratings incorporated in the plasmonic photoconductive detector.
shows the microscope image of the conventional and plasmonic photoconductive detector prototypes as well as the scanning electron microscope (SEM) image of the plasmonic contact electrode gratings of the plasmonic photoconductive detector prototype. The conventional and plasmonic photoconductive terahertz detector prototypes were then mounted on the same silicon lens and characterized under the same operation conditions.

The performance of the conventional and plasmonic photoconductive detector prototypes in response to an incident radiation from a commercially available photoconductive terahertz emitter (iPCA-21-05-1999-800-h) was characterized in a time-domain terahertz spectroscopy setup. A Ti:sapphire mode-locked laser with 200 fs pulses at 800 nm and 76 MHz repetition rate was used for pumping the photoconductive terahertz emitter and the photoconductive terahertz detector prototypes. First, the beam from the Ti:Sapphire mode-locked laser was split into a pump beam and a probe beam. Next, the pump and probe beams were focused onto the photoconductive terahertz emitter and detector prototypes, respectively. The emitted radiation from the photoconductive terahertz emitter was modulated by controlling bias voltage of the terahertz emitter, and subsequently focused onto the photoconductive terahertz detector prototypes by using two polyethylene spherical lenses. Finally, the output current of the photoconductive terahertz detector prototypes was measured by a lock-in amplifier with the terahertz radiation modulation reference. By inserting a controllable optical delay line in the optical pump path, the time delay between the optical probe and terahertz pulses was varied, and the time-domain output photocurrent of the photoconductive terahertz detector prototypes was measured accordingly. To achieve the highest output photocurrent levels from the photoconductive detector prototypes, the optical pump spot was focused asymmetrically onto the photoconductive gap and the optical pump polarization was set along the x-axis and y-axis for the conventional and plasmonic photoconductive detectors, respectively. Each measurement was repeated for various optical pump spot positions along the photoconductive gap until the highest output photocurrent level was achieved for each detector prototype.

The measured time-domain output photocurrent of the conventional and plasmonic photoconductive terahertz detectors, pumped by a 50 mW optical beam, is shown in Fig. 4(a)
Fig. 4 Measured output photocurrent of the conventional and plasmonic photoconductive detector prototypes in the (a) time-domain and (b) frequency-domain.
. While the output photocurrent of both photoconductive terahertz detectors follow the envelope of the received electric field from the photoconductive terahertz emitter used in the terahertz spectroscopy setup, 30 times higher output photocurrent levels are achieved by using the plasmonic photoconductive terahertz detectors. The frequency-domain output photocurrent of the photoconductive terahertz detector prototypes, obtained by calculating the Fourier transform of the measured time-domain output photocurrent, is shown in Fig. 4(b). The calculated output photocurrent spectra indicate that the 30 fold output photocurrent enhancement offered by the plasmonic photoconductive terahertz detector is maintained over 0.1-1.5 THz frequency range.

To compare the terahertz detection sensitivity of the conventional and plasmonic photoconductive detector prototypes, their output current noise is evaluated [38

38. N. Wang and M. Jarrahi, “Noise analysis of photoconductive terahertz detectors,” J. Infrared Milli. Terahz. Waves 34, (2013), doi:. [CrossRef]

]. The output current noise of each photoconductive detector prototype is calculated by measuring its output photocurrent spectra in the time-domain terahertz spectroscopy setup, while blocking the incident terahertz radiation from the photoconductive terahertz emitter. Figure 5(a)
Fig. 5 (a) The output current noise of the conventional and plasmonic photoconductive detector prototypes at 50 mW optical pump power, (b) The output noise level of the plasmonic photoconductive detector and (c) the conventional photoconductive detector at various optical pump power levels ranging from 10 mW to 80 mW.
shows the output current noise of the conventional and plasmonic photoconductive detector prototypes at a 50 mW optical pump power, indicating similar output current noise spectra for the conventional and plasmonic photoconductive detector prototypes. The same output noise level for the conventional and plasmonic photoconductive detector prototypes is due to the dominance of the Johnson–Nyquist noise rather than the photoconductor Shot noise in both photoconductive detector prototypes.

To further evaluate this hypothesis, the output current noise of the plasmonic and conventional photoconductive detectors are measured at various optical pump power levels ranging from 10 mW to 80 mW, as shown in Fig. 5(b) and Fig. 5(c). The measured output noise level of the plasmonic and conventional photoconductive detector prototypes show no dependence on the optical pump power level over the 10 – 80 mW pump power range, validating the dominance of the Johnson–Nyquist noise (rather than photoconductor Shot noise) in the device operation regime. Since both photoconductive detector prototypes have the same output current noise levels, the 30 fold responsivity enhancement offered by the plasmonic photoconductive detector enables achieving 30 times higher detection sensitivities over the 0.1-1.5 THz frequency band.

4. Conclusion

In conclusion, a photoconductive terahertz detector based on nanoscale plasmonic contact electrode gratings is presented and experimentally demonstrated. The presented plasmonic photoconductive detector addresses the quantum efficiency limitation of ultrafast photoconductors by significantly enhancing the concentration of the photo-generated carriers in close distances from photoconductor contact electrodes. Experimental results demonstrate that more than 30 times higher terahertz detection sensitivities can be achieved by a plasmonic photoconductive terahertz detector compared to comparable photoconductive terahertz detectors without plasmonic contact electrodes over 0.1-1.5 THz. The terahertz detection sensitivity enhancement offered by plasmonic photoconductive detectors in combination with the terahertz radiation power enhancement offered by plasmonic photoconductive emitters [39

39. C. W. Berry, N. Wang, M. R. Hashemi, M. Unlu, and M. Jarrahi, “Significant Performance Enhancement in Photoconductive Terahertz Optoelectronics by Incorporating Plasmonic Contact Electrodes,” Nat Commun 4, 1622 (2013). [CrossRef] [PubMed]

42

42. C. W. Berry and M. Jarrahi, “High-Performance Photoconductive Terahertz Sources Based on Nanoscale Contact Electrode Gratings,” Proc. IEEE Int. Microwave Symposium, 1–3, (2012). [CrossRef]

] would have a significant impact on future time-domain and frequency-domain terahertz imaging and spectroscopy systems by offering substantially higher signal-to-noise ratio levels.

Acknowledgment

The authors would like to thank Picometrix for providing the LT-GaAs substrate and gratefully acknowledge the financial support from Michigan Space Grant Consortium, DARPA Young Faculty Award (contract # N66001-10-1-4027), NSF CAREER Award (contract # N00014-11-1-0096), ONR Young Investigator Award (contract # N00014-12-1-0947), and ARO Young Investigator Award (contract # W911NF-12-1-0253).

References and links

1.

P. R. Smith, D. H. Auston, and M. C. Nuss, “Subpicosecond photoconducting dipole antennas,” IEEE J. Quantum Electron. 24(2), 255–260 (1988). [CrossRef]

2.

M. van Exter and D. Grischkowsky, “Characterization of an optoelectronic terahertz beam system,” IEEE Trans. Microw. Theory Tech. 38(11), 1684–1691 (1990). [CrossRef]

3.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, J. B. Stark, Q. Wu, X.-C. Zhang, and J. F. Federici, “Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection,” Appl. Phys. Lett. 73(4), 444–446 (1998). [CrossRef]

4.

F. G. Sun, G. A. Wagoner, and X.-C. Zhang, “Measurement of free-space terahertz pulses via long-lifetime Photoconductors,” Appl. Phys. Lett. 67(12), 1656–1658 (1995). [CrossRef]

5.

J. F. O’Hara, J. M. O. Zide, A. C. Gossard, A. J. Taylor, and R. D. Averitt, “Enhanced terahertz detection via ErAs:GaAs nanoisland superlattices,” Appl. Phys. Lett. 88(25), 251119 (2006). [CrossRef]

6.

M. Tani, K.-S. Lee, and X.-C. Zhang, “Detection of terahertz radiation with low-temperature-grown GaAs-based photoconductive antenna using 1.55 μm probe,” Appl. Phys. Lett. 77(9), 1396–1398 (2000). [CrossRef]

7.

T.-A. Liu, M. Tani, M. Nakajima, M. Hangyo, and C.-L. Pan, “Ultrabroadband terahertz field detection by photoconductive antennas based on multi-energy arsenic-ion-implanted GaAs and semi-insulating GaAs,” Appl. Phys. Lett. 83(7), 1322–1324 (2003). [CrossRef]

8.

M. Suzuki and M. Tonouchi, “Fe-implanted InGaAs photoconductive terahertz detectors triggered by 1.56 μm femtosecond optical pulses,” Appl. Phys. Lett. 86(16), 163504 (2005). [CrossRef]

9.

A. Takazato, M. Kamakura, T. Matsui, J. Kitagawa, and Y. Kadoya, “Terahertz wave emission and detection using photoconductive antennas made on low-temperature-grown InGaAs with 1.56 μm pulse excitation,” Appl. Phys. Lett. 91(1), 011102 (2007). [CrossRef]

10.

T.-A. Liu, M. Tani, M. Nakajima, M. Hangyo, K. Sakai, S.-I. Nakashima, and C.-L. Pan, “Ultrabroadband terahertz field detection by proton-bombarded InP photoconductive antennas,” Opt. Express 12(13), 2954–2959 (2004). [CrossRef] [PubMed]

11.

E. Castro-Camus, J. Lloyd-Hughes, M. B. Johnston, M. D. Fraser, H. H. Tan, and C. Jagadish, “Polarization-sensitive terahertz detection by multicontact photoconductive receivers,” Appl. Phys. Lett. 86(25), 254102 (2005). [CrossRef]

12.

F. Peter, S. Winnerl, S. Nitsche, A. Dreyhaupt, H. Schneider, and M. Helm, “Coherent terahertz detection with a large-area photoconductive antenna,” Appl. Phys. Lett. 91(8), 081109 (2007). [CrossRef]

13.

S. Liu, X. Shou, and A. Nahata, “Coherent Detection of Multiband Terahertz Radiation Using a Surface Plasmon-Polariton Based Photoconductive Antenna,” IEEE Trans. Terahertz Sci. Technol. 1(2), 412–415 (2011). [CrossRef]

14.

B. Heshmat, H. Pahlevaninezhad, Y. Pang, M. Masnadi-Shirazi, R. Burton Lewis, T. Tiedje, R. Gordon, and T. E. Darcie, “Nanoplasmonic Terahertz Photoconductive Switch on GaAs,” Nano Lett. 12(12), 6255–6259 (2012). [CrossRef] [PubMed]

15.

M. Tani, M. Herrmann, and K. Sakai, “Generation and detection of terahertz pulsed radiation with photoconductive antennas and its application to imaging,” Meas. Sci. Technol. 13(11), 1739–1745 (2002). [CrossRef]

16.

B. B. Hu and M. C. Nuss, “Imaging with terahertz waves,” Opt. Lett. 20(16), 1716–1718 (1995). [CrossRef] [PubMed]

17.

D. M. Mittleman, R. H. Jacobsen, and M. C. Nuss, “T-Ray imaging,” IEEE J. Sel. Top. Quantum Electron. 2(3), 679–692 (1996). [CrossRef]

18.

A. Markelz, S. Whitmire, J. Hillebrecht, and R. Birge, “THz time domain spectroscopy of biomolecular conformational modes,” Phys. Med. Biol. 47(21), 3797–3805 (2002). [CrossRef] [PubMed]

19.

D. D. Arnone, C. Ciesla, and M. Pepper, “Terahertz imaging comes into view,” Phys. World 13, 35–40 (2000).

20.

J. A. Zeitler, P. F. Taday, D. A. Newnham, M. Pepper, K. C. Gordon, and T. Rades, “Terahertz pulsed spectroscopy and imaging in the pharmaceutical setting--a review,” J. Pharm. Pharmacol. 59(2), 209–223 (2007). [CrossRef] [PubMed]

21.

D. G. Rowe, “Terahertz takes to the stage,” Nat. Photonics 1(2), 75–77 (2007). [CrossRef]

22.

M. C. Kemp, P. F. Taday, B. E. Cole, J. A. Cluff, A. J. Fitzgerald, and W. R. Tribe, “Security applications of terahertz technology,” Proc. SPIE 5070, 44–52 (2003). [CrossRef]

23.

S. Kono, M. Tani, and K. Sakai, “Coherent detection of mid-infrared radiation up to 60 THz with an LT-GaAs photoconductive antenna,” IEE Proc. Optoelectronics 149, 105- 109 (2002). [CrossRef]

24.

S. Verghese, K. A. McIntosh, S. Calawa, W. F. Dinatale, E. K. Duerr, and K. A. Molvar, “Generation and detection of coherent terahertz waves using two Photomixers,” Appl. Phys. Lett. 73(26), 3824–3826 (1998). [CrossRef]

25.

P. C. Upadhya, W. Fan, A. Burnett, J. Cunningham, A. G. Davies, E. H. Linfield, J. Lloyd-Hughes, E. Castro-Camus, M. B. Johnston, and H. Beere, “Excitation-density-dependent generation of broadband terahertz radiation in an asymmetrically excited photoconductive antenna,” Opt. Lett. 32(16), 2297–2299 (2007). [CrossRef] [PubMed]

26.

S. E. Ralph and D. Grischkowsky, “Trap‐enhanced electric fields in semi‐insulators: The role of electrical and optical carrier injection,” Appl. Phys. Lett. 59(16), 1972 (1991). [CrossRef]

27.

C. W. Berry and M. Jarrahi, “Principles of impedance matching in photoconductive antennas,” J. Infrared Milli. Terahz. Waves 33(12), 1182–1189 (2012). [CrossRef]

28.

J. Požela and A. Reklaitis, “Electron transport properties in GaAs at high electric fields,” Solid-State Electron. 23(9), 927–933 (1980). [CrossRef]

29.

C. W. Berry and M. Jarrahi, “Plasmonically-enhanced localization of light into photoconductive antennas,” Proc. Conf. Lasers and Electro-Optics, CFI2 (2010). [CrossRef]

30.

C. W. Berry and M. Jarrahi, “Ultrafast Photoconductors based on Plasmonic Gratings,” Proc. Int. Conf. Infrared, Millimeter, and Terahertz Waves, 1–2 (2011).

31.

B.-Y. Hsieh and M. Jarrahi, “Analysis of periodic metallic nano-slits for efficient interaction of terahertz and optical waves at nano-scale dimensions,” J. Appl. Phys. 109(8), 084326 (2011). [CrossRef]

32.

C. W. Berry, J. Moore, and M. Jarrahi, “Design of Reconfigurable Metallic Slits for Terahertz Beam Modulation,” Opt. Express 19(2), 1236–1245 (2011). [CrossRef] [PubMed]

33.

M. Beck, H. Schäfer, G. Klatt, J. Demsar, S. Winnerl, M. Helm, and T. Dekorsy, “Impulsive terahertz radiation with high electric fields from an amplifier-driven large-area photoconductive antenna,” Opt. Express 18(9), 9251–9257 (2010). [CrossRef] [PubMed]

34.

M. Jarrahi and T. H. Lee, “High power tunable terahertz generation based on photoconductive antenna arrays,” Proc. IEEE Int. Microwave Symposium, 391–394 (2008). [CrossRef]

35.

M. Jarrahi, “Terahertz radiation-band engineering through spatial beam-shaping,” IEEE Photon. Technol. Lett. 21(13), 2019620 (2009). [CrossRef]

36.

T. Hattori, K. Egawa, S. I. Ookuma, and T. Itatani, “Intense terahertz pulses from large-aperture antenna with interdigitated electrodes,” Jpn. J. Appl. Phys. 45(15), L422–L424 (2006). [CrossRef]

37.

A. Dreyhaupt, S. Winnerl, T. Dekorsy, and M. Helm, “High-intensity terahertz radiation from a microstructured large-area photoconductor,” Appl. Phys. Lett. 86(12), 121114 (2005). [CrossRef]

38.

N. Wang and M. Jarrahi, “Noise analysis of photoconductive terahertz detectors,” J. Infrared Milli. Terahz. Waves 34, (2013), doi:. [CrossRef]

39.

C. W. Berry, N. Wang, M. R. Hashemi, M. Unlu, and M. Jarrahi, “Significant Performance Enhancement in Photoconductive Terahertz Optoelectronics by Incorporating Plasmonic Contact Electrodes,” Nat Commun 4, 1622 (2013). [CrossRef] [PubMed]

40.

C. W. Berry and M. Jarrahi, “Terahertz generation using plasmonic photoconductive gratings,” New J. Phys. 14(10), 105029 (2012). [CrossRef]

41.

C. W. Berry and M. Jarrahi, “Plasmonic Photoconductive Antennas for High Power Terahertz Generation,” Proc. IEEE Int. Antennas and Propagation Symposium, 1–2 (2012). [CrossRef]

42.

C. W. Berry and M. Jarrahi, “High-Performance Photoconductive Terahertz Sources Based on Nanoscale Contact Electrode Gratings,” Proc. IEEE Int. Microwave Symposium, 1–3, (2012). [CrossRef]

OCIS Codes
(040.0040) Detectors : Detectors
(350.2770) Other areas of optics : Gratings
(250.5403) Optoelectronics : Plasmonics
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:
Detectors

History
Original Manuscript: April 30, 2013
Revised Manuscript: July 5, 2013
Manuscript Accepted: July 5, 2013
Published: July 11, 2013

Citation
Ning Wang, Mohammad R. Hashemi, and Mona Jarrahi, "Plasmonic photoconductive detectors for enhanced terahertz detection sensitivity," Opt. Express 21, 17221-17227 (2013)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-21-14-17221


Sort:  Author  |  Year  |  Journal  |  Reset  

References

  1. P. R. Smith, D. H. Auston, and M. C. Nuss, “Subpicosecond photoconducting dipole antennas,” IEEE J. Quantum Electron.24(2), 255–260 (1988). [CrossRef]
  2. M. van Exter and D. Grischkowsky, “Characterization of an optoelectronic terahertz beam system,” IEEE Trans. Microw. Theory Tech.38(11), 1684–1691 (1990). [CrossRef]
  3. Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, J. B. Stark, Q. Wu, X.-C. Zhang, and J. F. Federici, “Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection,” Appl. Phys. Lett.73(4), 444–446 (1998). [CrossRef]
  4. F. G. Sun, G. A. Wagoner, and X.-C. Zhang, “Measurement of free-space terahertz pulses via long-lifetime Photoconductors,” Appl. Phys. Lett.67(12), 1656–1658 (1995). [CrossRef]
  5. J. F. O’Hara, J. M. O. Zide, A. C. Gossard, A. J. Taylor, and R. D. Averitt, “Enhanced terahertz detection via ErAs:GaAs nanoisland superlattices,” Appl. Phys. Lett.88(25), 251119 (2006). [CrossRef]
  6. M. Tani, K.-S. Lee, and X.-C. Zhang, “Detection of terahertz radiation with low-temperature-grown GaAs-based photoconductive antenna using 1.55 μm probe,” Appl. Phys. Lett.77(9), 1396–1398 (2000). [CrossRef]
  7. T.-A. Liu, M. Tani, M. Nakajima, M. Hangyo, and C.-L. Pan, “Ultrabroadband terahertz field detection by photoconductive antennas based on multi-energy arsenic-ion-implanted GaAs and semi-insulating GaAs,” Appl. Phys. Lett.83(7), 1322–1324 (2003). [CrossRef]
  8. M. Suzuki and M. Tonouchi, “Fe-implanted InGaAs photoconductive terahertz detectors triggered by 1.56 μm femtosecond optical pulses,” Appl. Phys. Lett.86(16), 163504 (2005). [CrossRef]
  9. A. Takazato, M. Kamakura, T. Matsui, J. Kitagawa, and Y. Kadoya, “Terahertz wave emission and detection using photoconductive antennas made on low-temperature-grown InGaAs with 1.56 μm pulse excitation,” Appl. Phys. Lett.91(1), 011102 (2007). [CrossRef]
  10. T.-A. Liu, M. Tani, M. Nakajima, M. Hangyo, K. Sakai, S.-I. Nakashima, and C.-L. Pan, “Ultrabroadband terahertz field detection by proton-bombarded InP photoconductive antennas,” Opt. Express12(13), 2954–2959 (2004). [CrossRef] [PubMed]
  11. E. Castro-Camus, J. Lloyd-Hughes, M. B. Johnston, M. D. Fraser, H. H. Tan, and C. Jagadish, “Polarization-sensitive terahertz detection by multicontact photoconductive receivers,” Appl. Phys. Lett.86(25), 254102 (2005). [CrossRef]
  12. F. Peter, S. Winnerl, S. Nitsche, A. Dreyhaupt, H. Schneider, and M. Helm, “Coherent terahertz detection with a large-area photoconductive antenna,” Appl. Phys. Lett.91(8), 081109 (2007). [CrossRef]
  13. S. Liu, X. Shou, and A. Nahata, “Coherent Detection of Multiband Terahertz Radiation Using a Surface Plasmon-Polariton Based Photoconductive Antenna,” IEEE Trans. Terahertz Sci. Technol.1(2), 412–415 (2011). [CrossRef]
  14. B. Heshmat, H. Pahlevaninezhad, Y. Pang, M. Masnadi-Shirazi, R. Burton Lewis, T. Tiedje, R. Gordon, and T. E. Darcie, “Nanoplasmonic Terahertz Photoconductive Switch on GaAs,” Nano Lett.12(12), 6255–6259 (2012). [CrossRef] [PubMed]
  15. M. Tani, M. Herrmann, and K. Sakai, “Generation and detection of terahertz pulsed radiation with photoconductive antennas and its application to imaging,” Meas. Sci. Technol.13(11), 1739–1745 (2002). [CrossRef]
  16. B. B. Hu and M. C. Nuss, “Imaging with terahertz waves,” Opt. Lett.20(16), 1716–1718 (1995). [CrossRef] [PubMed]
  17. D. M. Mittleman, R. H. Jacobsen, and M. C. Nuss, “T-Ray imaging,” IEEE J. Sel. Top. Quantum Electron.2(3), 679–692 (1996). [CrossRef]
  18. A. Markelz, S. Whitmire, J. Hillebrecht, and R. Birge, “THz time domain spectroscopy of biomolecular conformational modes,” Phys. Med. Biol.47(21), 3797–3805 (2002). [CrossRef] [PubMed]
  19. D. D. Arnone, C. Ciesla, and M. Pepper, “Terahertz imaging comes into view,” Phys. World13, 35–40 (2000).
  20. J. A. Zeitler, P. F. Taday, D. A. Newnham, M. Pepper, K. C. Gordon, and T. Rades, “Terahertz pulsed spectroscopy and imaging in the pharmaceutical setting--a review,” J. Pharm. Pharmacol.59(2), 209–223 (2007). [CrossRef] [PubMed]
  21. D. G. Rowe, “Terahertz takes to the stage,” Nat. Photonics1(2), 75–77 (2007). [CrossRef]
  22. M. C. Kemp, P. F. Taday, B. E. Cole, J. A. Cluff, A. J. Fitzgerald, and W. R. Tribe, “Security applications of terahertz technology,” Proc. SPIE5070, 44–52 (2003). [CrossRef]
  23. S. Kono, M. Tani, and K. Sakai, “Coherent detection of mid-infrared radiation up to 60 THz with an LT-GaAs photoconductive antenna,” IEE Proc. Optoelectronics 149, 105- 109 (2002). [CrossRef]
  24. S. Verghese, K. A. McIntosh, S. Calawa, W. F. Dinatale, E. K. Duerr, and K. A. Molvar, “Generation and detection of coherent terahertz waves using two Photomixers,” Appl. Phys. Lett.73(26), 3824–3826 (1998). [CrossRef]
  25. P. C. Upadhya, W. Fan, A. Burnett, J. Cunningham, A. G. Davies, E. H. Linfield, J. Lloyd-Hughes, E. Castro-Camus, M. B. Johnston, and H. Beere, “Excitation-density-dependent generation of broadband terahertz radiation in an asymmetrically excited photoconductive antenna,” Opt. Lett.32(16), 2297–2299 (2007). [CrossRef] [PubMed]
  26. S. E. Ralph and D. Grischkowsky, “Trap‐enhanced electric fields in semi‐insulators: The role of electrical and optical carrier injection,” Appl. Phys. Lett.59(16), 1972 (1991). [CrossRef]
  27. C. W. Berry and M. Jarrahi, “Principles of impedance matching in photoconductive antennas,” J. Infrared Milli. Terahz. Waves33(12), 1182–1189 (2012). [CrossRef]
  28. J. Požela and A. Reklaitis, “Electron transport properties in GaAs at high electric fields,” Solid-State Electron.23(9), 927–933 (1980). [CrossRef]
  29. C. W. Berry and M. Jarrahi, “Plasmonically-enhanced localization of light into photoconductive antennas,” Proc. Conf. Lasers and Electro-Optics, CFI2 (2010). [CrossRef]
  30. C. W. Berry and M. Jarrahi, “Ultrafast Photoconductors based on Plasmonic Gratings,” Proc. Int. Conf. Infrared, Millimeter, and Terahertz Waves, 1–2 (2011).
  31. B.-Y. Hsieh and M. Jarrahi, “Analysis of periodic metallic nano-slits for efficient interaction of terahertz and optical waves at nano-scale dimensions,” J. Appl. Phys.109(8), 084326 (2011). [CrossRef]
  32. C. W. Berry, J. Moore, and M. Jarrahi, “Design of Reconfigurable Metallic Slits for Terahertz Beam Modulation,” Opt. Express19(2), 1236–1245 (2011). [CrossRef] [PubMed]
  33. M. Beck, H. Schäfer, G. Klatt, J. Demsar, S. Winnerl, M. Helm, and T. Dekorsy, “Impulsive terahertz radiation with high electric fields from an amplifier-driven large-area photoconductive antenna,” Opt. Express18(9), 9251–9257 (2010). [CrossRef] [PubMed]
  34. M. Jarrahi and T. H. Lee, “High power tunable terahertz generation based on photoconductive antenna arrays,” Proc. IEEE Int. Microwave Symposium, 391–394 (2008). [CrossRef]
  35. M. Jarrahi, “Terahertz radiation-band engineering through spatial beam-shaping,” IEEE Photon. Technol. Lett.21(13), 2019620 (2009). [CrossRef]
  36. T. Hattori, K. Egawa, S. I. Ookuma, and T. Itatani, “Intense terahertz pulses from large-aperture antenna with interdigitated electrodes,” Jpn. J. Appl. Phys.45(15), L422–L424 (2006). [CrossRef]
  37. A. Dreyhaupt, S. Winnerl, T. Dekorsy, and M. Helm, “High-intensity terahertz radiation from a microstructured large-area photoconductor,” Appl. Phys. Lett.86(12), 121114 (2005). [CrossRef]
  38. N. Wang and M. Jarrahi, “Noise analysis of photoconductive terahertz detectors,” J. Infrared Milli. Terahz. Waves34, (2013), doi:. [CrossRef]
  39. C. W. Berry, N. Wang, M. R. Hashemi, M. Unlu, and M. Jarrahi, “Significant Performance Enhancement in Photoconductive Terahertz Optoelectronics by Incorporating Plasmonic Contact Electrodes,” Nat Commun4, 1622 (2013). [CrossRef] [PubMed]
  40. C. W. Berry and M. Jarrahi, “Terahertz generation using plasmonic photoconductive gratings,” New J. Phys.14(10), 105029 (2012). [CrossRef]
  41. C. W. Berry and M. Jarrahi, “Plasmonic Photoconductive Antennas for High Power Terahertz Generation,” Proc. IEEE Int. Antennas and Propagation Symposium, 1–2 (2012). [CrossRef]
  42. C. W. Berry and M. Jarrahi, “High-Performance Photoconductive Terahertz Sources Based on Nanoscale Contact Electrode Gratings,” Proc. IEEE Int. Microwave Symposium, 1–3, (2012). [CrossRef]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

Figures

Fig. 1 Fig. 2 Fig. 3
 
Fig. 4 Fig. 5
 

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited