OSA's Digital Library

Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. 8 — Apr. 11, 2011
  • pp: 7695–7704

Thermally excited near-field radiation and far-field interference

Yusuke Kajihara, Keishi Kosaka, and Susumu Komiyama  »View Author Affiliations

Optics Express, Vol. 19, Issue 8, pp. 7695-7704 (2011)

View Full Text Article

Enhanced HTML    Acrobat PDF (1928 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Thermal radiation from samples of Au layers patterned on GaAs, SiO2, and SiC at 300 K are studied with a scattering-type scanning near-field optical microscope (wavelength: ~14.5 μm), without applying external illumination. Clear near-field images are obtained with a spatial resolution of ~60 nm. All the near field signals derived from different demodulation procedures decrease rapidly with increasing probe height h with characteristic decay lengths of 40 ~60 nm. Near-field images are free from any signature of in-plane spatial interference. The findings are accounted for by theoretically expected surface evanescent waves, which are thermally excited in the close vicinity of material surfaces. Outside the near-field zone (1 μm < h), signals reappear and vary as a sinusoidal function of h, exhibiting a standing wave-like interference pattern. These far-field signals are ascribed to the effect of weak ambient radiation.

© 2011 OSA

OCIS Codes
(110.3080) Imaging systems : Infrared imaging
(110.6820) Imaging systems : Thermal imaging
(260.3160) Physical optics : Interference
(180.4243) Microscopy : Near-field microscopy

ToC Category:

Original Manuscript: February 3, 2011
Revised Manuscript: March 19, 2011
Manuscript Accepted: March 22, 2011
Published: April 6, 2011

Yusuke Kajihara, Keishi Kosaka, and Susumu Komiyama, "Thermally excited near-field radiation and far-field interference," Opt. Express 19, 7695-7704 (2011)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. As a review, see for exampleK. Joulain, J.-P. Mulet, F. Marquier, R. Carminati, and J.-J. Greffet, “Surface electromagnetic waves thermally excited: Radiative heat transfer, coherence properties and Casimir forces revisited in the near field,” Surf. Sci. Rep. 57(3-4), 59–112 (2005). [CrossRef]
  2. K. Joulain, R. Carminati, J.-P. Mulet, and J.-J. Greffet, “Definition and measurement of the local density of electromagnetic states close to an interface,” Phys. Rev. B 68(24), 245405 (2003). [CrossRef]
  3. A. V. Shchegrov, K. Joulain, R. Carminati, and J.-J. Greffet, “Near-field spectral effects due to electromagnetic surface excitations,” Phys. Rev. Lett. 85(7), 1548–1551 (2000). [CrossRef] [PubMed]
  4. E. Rousseau, A. Siria, G. Jourdan, S. Volz, F. Comin, J. Chevrier, and J.-J. Greffet, “Radiative heat transfer at the nanoscale,” Nat. Photonics 3(9), 514–517 (2009). [CrossRef]
  5. S. Shen, A. Narayanaswamy, and G. Chen, “Surface phonon polaritons mediated energy transfer between nanoscale gaps,” Nano Lett. 9(8), 2909–2913 (2009). [CrossRef] [PubMed]
  6. F. Zenhausern, M. P. O’Boyle, and H. K. Wickramasinghe, “Apertureless near-field optical microscope,” Appl. Phys. Lett. 65(13), 1623 (1994). [CrossRef]
  7. Y. Inouye and S. Kawata, “Near-field scanning optical microscope with a metallic probe tip,” Opt. Lett. 19(3), 159–161 (1994). [CrossRef] [PubMed]
  8. B. Knoll and F. Keilmann, “Near-field probing of vibrational absorption for chemical microscopy,” Nature 399(6732), 134–137 (1999). [CrossRef]
  9. R. Hillenbrand, T. Taubner, and F. Keilmann, “Phonon-enhanced light matter interaction at the nanometre scale,” Nature 418(6894), 159–162 (2002). [CrossRef] [PubMed]
  10. Y. De Wilde, F. Formanek, R. Carminati, B. Gralak, P. A. Lemoine, K. Joulain, J. P. Mulet, Y. Chen, and J.-J. Greffet, “Thermal radiation scanning tunnelling microscopy,” Nature 444(7120), 740–743 (2006). [CrossRef] [PubMed]
  11. Y. Kajihara, K. Kosaka, and S. Komiyama, “A sensitive near-field microscope for thermal radiation,” Rev. Sci. Instrum. 81(3), 033706 (2010). [CrossRef] [PubMed]
  12. T. Ueda, Z. An, K. Hirakawa, and S. Komiyama, “Charge-sensitive infrared phototransistors: Characterization by an all-cryogenic spectrometer,” J. Appl. Phys. 103(9), 093109 (2008). [CrossRef]
  13. As a review, seeS. Komiyama, “Single-photon detectors in the terahertz range,” IEEE J. Sel. Top. Quantum Electron. 17(1), 54–66 (2011). [CrossRef]
  14. Y. Kajihara, S. Komiyama, P. Nickels, and T. Ueda, “A passive long-wavelength infrared microscope with a highly sensitive phototransistor,” Rev. Sci. Instrum. 80(6), 063702 (2009). [CrossRef] [PubMed]
  15. Different strengths of noise are caused mainly by inhomogeneity of crystals.
  16. K. Karrai and R. D. Grober, “Piezoelectric tip-sample distance control for near field optical microscopes,” Appl. Phys. Lett. 66(14), 1842–1844 (1995). [CrossRef]
  17. For signal modulation, fTF = 32.7 kHz is too high for the high performance of CSIP detectors so that fM = 10 Hz is applied.
  18. We derived theoretical profiles from the electromagnetic local density of states (LDOS, [2]) by considering the scattering efficiency in terms of the point-dipole model [19]. The derived theoretical profile agrees relatively well with the experimental results. For quantitative comparison, however, it remains some ambiguity as to the scattering efficiency.
  19. B. Knoll and F. Keilmann, “Enhanced dielectric contrast in scattering-type scanning near-field optical microscopy,” Opt. Commun. 182(4-6), 321–328 (2000). [CrossRef]
  20. As discussed in [19], scattering amplitude of a probe rapidly decreases with h in a range 0 < h < R (radius of apex curvature), which would cause the signals I0, If, and I2f to rapidly decrease. Nevertheless, if the near-field contains a long-extending component, I0 and If will have additional slow decay components.
  21. The LDOS is theoretically discussed in [2], which predicts the LDOS (z = 50 nm) on Au is more than 10 times larger than those on the dielectrics (SiC, GaAs, SiO2). The discrepancy with the experimental values arises from the isotropic model of [2]. Larger experimental values certainly arise from the piezoelectric acoustic phonon modes that are not considered in the theoretical treatment.
  22. The near-field signal If near the surface in Fig. 4(a) is a little smaller than that in Fig. 3. The difference is attributed mainly to the probe condition. The signal change is not the problem because the signal characteristics like signal ratio between different materials are independent of the probe condition.
  23. F. Formanek, Y. De Wilde, and L. Aigouy, “Analysis of the measured signals in apertureless near-field optical microscopy,” Ultramicroscopy 103(2), 133–139 (2005). [CrossRef] [PubMed]
  24. P. G. Gucciardi, G. Bachelier, and M. Allegrini, “Far-field background suppression in tip-modulated apertureless near-field optical microscopy,” J. Appl. Phys. 99(12), 124309 (2006). [CrossRef]
  25. The effective radiation temperature, Tradiation is estimated by comparing the far-field radiation intensities from 77K-liquid nitrogen, 300K-Au and 300K-SiO2. We can derive Tradiation by knowing the emissivity and the reflectivity of each material and noting that Tradiation and Tsample are respectively relevant to the reflected and the emitted radiations.
  26. M. Born, and E. Wolf, Principles of Optics, 7th edition, (Cambridge Univ. Press, Cambridge, 1999).
  27. s ~π + 0.0005 should be taken if a sphere dipole model is assumed as in [19].
  28. J. C. Brice, Properties of Gallium Arsenide, 2nd edition, (INSPEC, London, 1990).
  29. M. Wakaki, K. Kudo, and T. Shibuya, Physical Properties and Data of Optical Materials, (CRC Press, Boca Raton, 2007).
  30. Thermodynamics requires that the interference pattern is visible when Tsample ≠ Tradiation but vanishes in thermal equilibrium, and that it reverses its sign according as Tsample > Tradiation or Tsample < Tradiation. The experimental values shown in Figs. 4–6 are opposite in sign to Relation (2) because Tsample > Tradiation.
  31. The probe tip in [10] is modulated in tapping mode at a frequency much higher than 10 Hz. It is difficult, however, to ascribe the discrepancies to the different method of tip modulation.

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.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited