Abstract

We introduce a new concept of spectroscopic near-field optical microscopy that records broad infrared spectra at each pixel during scanning. Two coherent beams with harmonic frequency-comb spectra are employed, one for illuminating the scanning tip, the other as reference for multi-heterodyne detection of the scattered light. Our implementation yields 200 cm-1 wide amplitude and phase spectra centered at 950 cm-1 (this band can be tuned between 700 and 1400 cm-1). We introduce a new technique of background suppression enabled by the short, 10 µs “snapshot” acquisition of infrared spectra which allows time-resolving the tapping motion. Thus we demonstrate broad-band mid-infrared near-field imaging that is essentially free of background artefacts.

© 2006 Optical Society of America

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2006 (3)

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nanoletters 6, 1307-1310 (2006).
[CrossRef]

A. Huber, N. Ocelic, T. Taubner, and R. Hillenbrand, "Nanoscale resolved infrared probing of crystal structure and of plasmon-phonon coupling," Nanoletters 6, 774-778 (2006).
[CrossRef]

A. Bartels, A. Thoma, C. Janke, T. Dekorsy, A. Dreyhaupt, S. Winnerl, and M. Helm, "High-resolution THz spectrometer with kHz scan rates," Opt. Express 14, 430-437 (2006).
[CrossRef] [PubMed]

2005 (1)

2004 (10)

F. Keilmann, C. Gohle, and R. Holzwarth, "Time-domain mid-infrared frequency-comb spectrometer," Opt. Lett. 29, 1542-1544 (2004).
[CrossRef] [PubMed]

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

K. Liu, J. Xu, and X. Zhang, "GaSe crystals for broadband terahertz wave detection," Appl. Phys. Lett. 85, 863-865 (2004).
[CrossRef]

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nanoletters 4, 1669-1672 (2004).
[CrossRef]

N. Ocelic and R. Hillenbrand, "Subwavelength-scale tailoring of surface phonon polaritons by focused ion-beam implementation," Nature Materials 3, 606-609 (2004).
[CrossRef] [PubMed]

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

F. Keilmann and R. Hillenbrand, "Near-field microscopy by elastic light scattering from a tip," Philos. Trans. R. Soc. London A 362, 787-805 (2004).
[CrossRef]

C. Kübler, R. Huber, S. T¨ubel, and A. Leitenstorfer, "Ultrabroadband detection of multi-terahertz field transients with GaSe electro-optic sensors: Approaching the near infrared," Appl. Phys. Lett. 85, 3360-3362 (2004).
[CrossRef]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Nanoscale polymer recognition by spectral signature in scattering infrared near-field microscopy," Appl. Phys. Lett. 85, 5064-5066 (2004).
[CrossRef]

2003 (1)

T. Taubner, R. Hillenbrand, and F. Keilmann, "Performance of visible and mid-infrared scattering-type near-field optical microscopes," J. Microsc. 210, 311-314 (2003).
[CrossRef] [PubMed]

2002 (3)

R. Hillenbrand and F. Keilmann, "Material-specific mapping of metal/semiconductor/dielectric nanosystems at 10 nm resolution by back-scattering near-field optical microscopy," Appl. Phys. Lett. 80, 25-27 (2002).
[CrossRef]

R. Hillenbrand, T. Taubner, and F. Keilmann, "Phonon-enhanced light-matter interaction at the nanometre scale," Nature 418, 159-162 (2002).
[CrossRef] [PubMed]

A. Semenov, G. Goltsman, and R. Sobolewski, "Hot-electron effect in superconductors and its applications for radiation sensors," Supercond. Sci. Technol. 15, R1-R16 (2002).
[CrossRef]

2001 (1)

R. Hillenbrand, B. Knoll, and F. Keilmann, "Pure optical contrast in scattering-type scanning near-field optical microscopy," J. Microsc. 202, 77-83 (2001).
[CrossRef] [PubMed]

2000 (6)

R. Stöckle, Y. Suh, V. Deckert, and R. Zenobi, "Nanoscale chemical analysis by tip-enhanced Raman spectroscopy," Chem. Phys. Lett. 318, 131-136 (2000).
[CrossRef]

B. Knoll and F. Keilmann, "Infrared conductivity mapping for nanoelectronics," Appl. Phys. Lett. 77, 3980-3982 (2000).
[CrossRef]

D. van der Weide, J. Murakowski, and F. Keilmann, "Gas-absorption spectroscopy with electronic Terahertz techniques," IEEE Trans. Microwave Theory Tech. 48, 740-743 (2000).
[CrossRef]

B. Knoll and F. Keilmann, "Enhanced dielectric contrast in scattering-type scanning near-field optical microscopy," Opt. Commun. 182, 321-328 (2000).
[CrossRef]

R. Huber, A. Brodschelm, F. Tauser, and A. Leitenstorfer, "Generation and field-resolved detection of femtosecond electromagnetic pulses tunable up to 41 THz," Appl. Phys. Lett. 76, 3191-3193 (2000).
[CrossRef]

R. Hillenbrand and F. Keilmann, "Complex optical constants on a subwavelength scale," Phys. Rev. Lett. 85, 3029-3032 (2000).
[CrossRef] [PubMed]

1999 (2)

B. Knoll and F. Keilmann, "Near-field probing of vibrational absorption for chemical microscopy," Nature 399, 134-137 (1999).
[CrossRef]

R. Kaindl, F. Eickemeyer, M. Woerner, and T. Elsaesser, "Broadband phase-matched difference frequency mixing of femtosecond pulses in GaSe: Experiment and theory," Appl. Phys. Lett. 75, 1060-1062 (1999).
[CrossRef]

1996 (1)

1995 (1)

F. Zenhausern, Y. Martin, and H. Wickramasinghe, "Scanning interferometric apertureless microscopy: optical imaging at 10 Angstrom resolution," Science 269, 1083-1085 (1995).
[CrossRef] [PubMed]

1987 (1)

1985 (1)

Aigouy, L.

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Allakhverdiev, K.

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

Bachelot, R.

Baran, O.

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

Bartels, A.

Boccara, A. C.

Brehm, M.

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nanoletters 6, 1307-1310 (2006).
[CrossRef]

A. Schliesser, M. Brehm, and F. Keilmann, "Frequency-comb infrared spectrometer for rapid, remote chemical sensing," Opt. Express 13, 9029-9038 (2005).
[CrossRef] [PubMed]

Brodschelm, A.

R. Huber, A. Brodschelm, F. Tauser, and A. Leitenstorfer, "Generation and field-resolved detection of femtosecond electromagnetic pulses tunable up to 41 THz," Appl. Phys. Lett. 76, 3191-3193 (2000).
[CrossRef]

Chen, Y.

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Chulkova, G.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Currie, M.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Deckert, V.

R. Stöckle, Y. Suh, V. Deckert, and R. Zenobi, "Nanoscale chemical analysis by tip-enhanced Raman spectroscopy," Chem. Phys. Lett. 318, 131-136 (2000).
[CrossRef]

Dekorsy, T.

DeWilde, Y.

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Dreyhaupt, A.

Eickemeyer, F.

R. Kaindl, F. Eickemeyer, M. Woerner, and T. Elsaesser, "Broadband phase-matched difference frequency mixing of femtosecond pulses in GaSe: Experiment and theory," Appl. Phys. Lett. 75, 1060-1062 (1999).
[CrossRef]

Elsaesser, T.

R. Kaindl, F. Eickemeyer, M. Woerner, and T. Elsaesser, "Broadband phase-matched difference frequency mixing of femtosecond pulses in GaSe: Experiment and theory," Appl. Phys. Lett. 75, 1060-1062 (1999).
[CrossRef]

Elzinga, P.

Formanek, F.

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Gleyzes, P.

Gohle, C.

Goltsman, G.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

A. Semenov, G. Goltsman, and R. Sobolewski, "Hot-electron effect in superconductors and its applications for radiation sensors," Supercond. Sci. Technol. 15, R1-R16 (2002).
[CrossRef]

Guseinova, D.

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

Helm, M.

Hillenbrand, R.

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nanoletters 6, 1307-1310 (2006).
[CrossRef]

A. Huber, N. Ocelic, T. Taubner, and R. Hillenbrand, "Nanoscale resolved infrared probing of crystal structure and of plasmon-phonon coupling," Nanoletters 6, 774-778 (2006).
[CrossRef]

F. Keilmann and R. Hillenbrand, "Near-field microscopy by elastic light scattering from a tip," Philos. Trans. R. Soc. London A 362, 787-805 (2004).
[CrossRef]

N. Ocelic and R. Hillenbrand, "Subwavelength-scale tailoring of surface phonon polaritons by focused ion-beam implementation," Nature Materials 3, 606-609 (2004).
[CrossRef] [PubMed]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Nanoscale polymer recognition by spectral signature in scattering infrared near-field microscopy," Appl. Phys. Lett. 85, 5064-5066 (2004).
[CrossRef]

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nanoletters 4, 1669-1672 (2004).
[CrossRef]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Performance of visible and mid-infrared scattering-type near-field optical microscopes," J. Microsc. 210, 311-314 (2003).
[CrossRef] [PubMed]

R. Hillenbrand and F. Keilmann, "Material-specific mapping of metal/semiconductor/dielectric nanosystems at 10 nm resolution by back-scattering near-field optical microscopy," Appl. Phys. Lett. 80, 25-27 (2002).
[CrossRef]

R. Hillenbrand, T. Taubner, and F. Keilmann, "Phonon-enhanced light-matter interaction at the nanometre scale," Nature 418, 159-162 (2002).
[CrossRef] [PubMed]

R. Hillenbrand, B. Knoll, and F. Keilmann, "Pure optical contrast in scattering-type scanning near-field optical microscopy," J. Microsc. 202, 77-83 (2001).
[CrossRef] [PubMed]

R. Hillenbrand and F. Keilmann, "Complex optical constants on a subwavelength scale," Phys. Rev. Lett. 85, 3029-3032 (2000).
[CrossRef] [PubMed]

Holzwarth, R.

Huber, A.

A. Huber, N. Ocelic, T. Taubner, and R. Hillenbrand, "Nanoscale resolved infrared probing of crystal structure and of plasmon-phonon coupling," Nanoletters 6, 774-778 (2006).
[CrossRef]

Huber, R.

C. Kübler, R. Huber, S. T¨ubel, and A. Leitenstorfer, "Ultrabroadband detection of multi-terahertz field transients with GaSe electro-optic sensors: Approaching the near infrared," Appl. Phys. Lett. 85, 3360-3362 (2004).
[CrossRef]

R. Huber, A. Brodschelm, F. Tauser, and A. Leitenstorfer, "Generation and field-resolved detection of femtosecond electromagnetic pulses tunable up to 41 THz," Appl. Phys. Lett. 76, 3191-3193 (2000).
[CrossRef]

Janke, C.

Jiang, Y.

Kaindl, R.

R. Kaindl, F. Eickemeyer, M. Woerner, and T. Elsaesser, "Broadband phase-matched difference frequency mixing of femtosecond pulses in GaSe: Experiment and theory," Appl. Phys. Lett. 75, 1060-1062 (1999).
[CrossRef]

Keilmann, F.

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nanoletters 6, 1307-1310 (2006).
[CrossRef]

A. Schliesser, M. Brehm, and F. Keilmann, "Frequency-comb infrared spectrometer for rapid, remote chemical sensing," Opt. Express 13, 9029-9038 (2005).
[CrossRef] [PubMed]

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nanoletters 4, 1669-1672 (2004).
[CrossRef]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Nanoscale polymer recognition by spectral signature in scattering infrared near-field microscopy," Appl. Phys. Lett. 85, 5064-5066 (2004).
[CrossRef]

F. Keilmann and R. Hillenbrand, "Near-field microscopy by elastic light scattering from a tip," Philos. Trans. R. Soc. London A 362, 787-805 (2004).
[CrossRef]

F. Keilmann, C. Gohle, and R. Holzwarth, "Time-domain mid-infrared frequency-comb spectrometer," Opt. Lett. 29, 1542-1544 (2004).
[CrossRef] [PubMed]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Performance of visible and mid-infrared scattering-type near-field optical microscopes," J. Microsc. 210, 311-314 (2003).
[CrossRef] [PubMed]

R. Hillenbrand and F. Keilmann, "Material-specific mapping of metal/semiconductor/dielectric nanosystems at 10 nm resolution by back-scattering near-field optical microscopy," Appl. Phys. Lett. 80, 25-27 (2002).
[CrossRef]

R. Hillenbrand, T. Taubner, and F. Keilmann, "Phonon-enhanced light-matter interaction at the nanometre scale," Nature 418, 159-162 (2002).
[CrossRef] [PubMed]

R. Hillenbrand, B. Knoll, and F. Keilmann, "Pure optical contrast in scattering-type scanning near-field optical microscopy," J. Microsc. 202, 77-83 (2001).
[CrossRef] [PubMed]

D. van der Weide, J. Murakowski, and F. Keilmann, "Gas-absorption spectroscopy with electronic Terahertz techniques," IEEE Trans. Microwave Theory Tech. 48, 740-743 (2000).
[CrossRef]

R. Hillenbrand and F. Keilmann, "Complex optical constants on a subwavelength scale," Phys. Rev. Lett. 85, 3029-3032 (2000).
[CrossRef] [PubMed]

B. Knoll and F. Keilmann, "Infrared conductivity mapping for nanoelectronics," Appl. Phys. Lett. 77, 3980-3982 (2000).
[CrossRef]

B. Knoll and F. Keilmann, "Enhanced dielectric contrast in scattering-type scanning near-field optical microscopy," Opt. Commun. 182, 321-328 (2000).
[CrossRef]

B. Knoll and F. Keilmann, "Near-field probing of vibrational absorption for chemical microscopy," Nature 399, 134-137 (1999).
[CrossRef]

King, G.

Kneisler, R.

Knoll, B.

R. Hillenbrand, B. Knoll, and F. Keilmann, "Pure optical contrast in scattering-type scanning near-field optical microscopy," J. Microsc. 202, 77-83 (2001).
[CrossRef] [PubMed]

B. Knoll and F. Keilmann, "Enhanced dielectric contrast in scattering-type scanning near-field optical microscopy," Opt. Commun. 182, 321-328 (2000).
[CrossRef]

B. Knoll and F. Keilmann, "Infrared conductivity mapping for nanoelectronics," Appl. Phys. Lett. 77, 3980-3982 (2000).
[CrossRef]

B. Knoll and F. Keilmann, "Near-field probing of vibrational absorption for chemical microscopy," Nature 399, 134-137 (1999).
[CrossRef]

Korneev, A.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Kouminov, P.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Kübler, C.

C. Kübler, R. Huber, S. T¨ubel, and A. Leitenstorfer, "Ultrabroadband detection of multi-terahertz field transients with GaSe electro-optic sensors: Approaching the near infrared," Appl. Phys. Lett. 85, 3360-3362 (2004).
[CrossRef]

Kulibekov, A.

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

Kwok, W.K.

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Lahrech, A.

Lauredeau, N.

Leitenstorfer, A.

R. Huber, A. Brodschelm, F. Tauser, and A. Leitenstorfer, "Generation and field-resolved detection of femtosecond electromagnetic pulses tunable up to 41 THz," Appl. Phys. Lett. 76, 3191-3193 (2000).
[CrossRef]

Liu, K.

K. Liu, J. Xu, and X. Zhang, "GaSe crystals for broadband terahertz wave detection," Appl. Phys. Lett. 85, 863-865 (2004).
[CrossRef]

Lo, W.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Lytle, F.

Martin, Y.

F. Zenhausern, Y. Martin, and H. Wickramasinghe, "Scanning interferometric apertureless microscopy: optical imaging at 10 Angstrom resolution," Science 269, 1083-1085 (1995).
[CrossRef] [PubMed]

Matvienko, V.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Murakowski, J.

D. van der Weide, J. Murakowski, and F. Keilmann, "Gas-absorption spectroscopy with electronic Terahertz techniques," IEEE Trans. Microwave Theory Tech. 48, 740-743 (2000).
[CrossRef]

Ocelic, N.

A. Huber, N. Ocelic, T. Taubner, and R. Hillenbrand, "Nanoscale resolved infrared probing of crystal structure and of plasmon-phonon coupling," Nanoletters 6, 774-778 (2006).
[CrossRef]

N. Ocelic and R. Hillenbrand, "Subwavelength-scale tailoring of surface phonon polaritons by focused ion-beam implementation," Nature Materials 3, 606-609 (2004).
[CrossRef] [PubMed]

Paulius, L.

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Pearlman, A.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Salaev, E.

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

Schliesser, A.

Semenov, A.

A. Semenov, G. Goltsman, and R. Sobolewski, "Hot-electron effect in superconductors and its applications for radiation sensors," Supercond. Sci. Technol. 15, R1-R16 (2002).
[CrossRef]

Slysz, W.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Smirnov, K.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Sobolewski, R.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

A. Semenov, G. Goltsman, and R. Sobolewski, "Hot-electron effect in superconductors and its applications for radiation sensors," Supercond. Sci. Technol. 15, R1-R16 (2002).
[CrossRef]

Stöckle, R.

R. Stöckle, Y. Suh, V. Deckert, and R. Zenobi, "Nanoscale chemical analysis by tip-enhanced Raman spectroscopy," Chem. Phys. Lett. 318, 131-136 (2000).
[CrossRef]

Suh, Y.

R. Stöckle, Y. Suh, V. Deckert, and R. Zenobi, "Nanoscale chemical analysis by tip-enhanced Raman spectroscopy," Chem. Phys. Lett. 318, 131-136 (2000).
[CrossRef]

Taubner, T.

A. Huber, N. Ocelic, T. Taubner, and R. Hillenbrand, "Nanoscale resolved infrared probing of crystal structure and of plasmon-phonon coupling," Nanoletters 6, 774-778 (2006).
[CrossRef]

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nanoletters 6, 1307-1310 (2006).
[CrossRef]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Nanoscale polymer recognition by spectral signature in scattering infrared near-field microscopy," Appl. Phys. Lett. 85, 5064-5066 (2004).
[CrossRef]

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nanoletters 4, 1669-1672 (2004).
[CrossRef]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Performance of visible and mid-infrared scattering-type near-field optical microscopes," J. Microsc. 210, 311-314 (2003).
[CrossRef] [PubMed]

R. Hillenbrand, T. Taubner, and F. Keilmann, "Phonon-enhanced light-matter interaction at the nanometre scale," Nature 418, 159-162 (2002).
[CrossRef] [PubMed]

Tauser, F.

R. Huber, A. Brodschelm, F. Tauser, and A. Leitenstorfer, "Generation and field-resolved detection of femtosecond electromagnetic pulses tunable up to 41 THz," Appl. Phys. Lett. 76, 3191-3193 (2000).
[CrossRef]

Thoma, A.

van der Weide, D.

D. van der Weide, J. Murakowski, and F. Keilmann, "Gas-absorption spectroscopy with electronic Terahertz techniques," IEEE Trans. Microwave Theory Tech. 48, 740-743 (2000).
[CrossRef]

Verevkin, A.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Voronov, B.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Wessel, J.

Wickramasinghe, H.

F. Zenhausern, Y. Martin, and H. Wickramasinghe, "Scanning interferometric apertureless microscopy: optical imaging at 10 Angstrom resolution," Science 269, 1083-1085 (1995).
[CrossRef] [PubMed]

Wilsher, K.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Winnerl, S.

Woerner, M.

R. Kaindl, F. Eickemeyer, M. Woerner, and T. Elsaesser, "Broadband phase-matched difference frequency mixing of femtosecond pulses in GaSe: Experiment and theory," Appl. Phys. Lett. 75, 1060-1062 (1999).
[CrossRef]

Xu, J.

K. Liu, J. Xu, and X. Zhang, "GaSe crystals for broadband terahertz wave detection," Appl. Phys. Lett. 85, 863-865 (2004).
[CrossRef]

Zenhausern, F.

F. Zenhausern, Y. Martin, and H. Wickramasinghe, "Scanning interferometric apertureless microscopy: optical imaging at 10 Angstrom resolution," Science 269, 1083-1085 (1995).
[CrossRef] [PubMed]

Zenobi, R.

R. Stöckle, Y. Suh, V. Deckert, and R. Zenobi, "Nanoscale chemical analysis by tip-enhanced Raman spectroscopy," Chem. Phys. Lett. 318, 131-136 (2000).
[CrossRef]

Zhang, J.

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

Zhang, X.

K. Liu, J. Xu, and X. Zhang, "GaSe crystals for broadband terahertz wave detection," Appl. Phys. Lett. 85, 863-865 (2004).
[CrossRef]

Appl. Opt. (1)

Appl. Phys. Lett. (8)

B. Knoll and F. Keilmann, "Infrared conductivity mapping for nanoelectronics," Appl. Phys. Lett. 77, 3980-3982 (2000).
[CrossRef]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Nanoscale polymer recognition by spectral signature in scattering infrared near-field microscopy," Appl. Phys. Lett. 85, 5064-5066 (2004).
[CrossRef]

R. Kaindl, F. Eickemeyer, M. Woerner, and T. Elsaesser, "Broadband phase-matched difference frequency mixing of femtosecond pulses in GaSe: Experiment and theory," Appl. Phys. Lett. 75, 1060-1062 (1999).
[CrossRef]

R. Huber, A. Brodschelm, F. Tauser, and A. Leitenstorfer, "Generation and field-resolved detection of femtosecond electromagnetic pulses tunable up to 41 THz," Appl. Phys. Lett. 76, 3191-3193 (2000).
[CrossRef]

C. Kübler, R. Huber, S. T¨ubel, and A. Leitenstorfer, "Ultrabroadband detection of multi-terahertz field transients with GaSe electro-optic sensors: Approaching the near infrared," Appl. Phys. Lett. 85, 3360-3362 (2004).
[CrossRef]

R. Hillenbrand and F. Keilmann, "Material-specific mapping of metal/semiconductor/dielectric nanosystems at 10 nm resolution by back-scattering near-field optical microscopy," Appl. Phys. Lett. 80, 25-27 (2002).
[CrossRef]

A. Korneev, P. Kouminov, V. Matvienko, G. Chulkova, K. Smirnov, B. Voronov, G. Goltsman, M. Currie, W. Lo, K. Wilsher, J. Zhang,W. Slysz, A. Pearlman, A. Verevkin, and R. Sobolewski, "Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors," Appl. Phys. Lett. 84, 5338-5340 (2004).
[CrossRef]

K. Liu, J. Xu, and X. Zhang, "GaSe crystals for broadband terahertz wave detection," Appl. Phys. Lett. 85, 863-865 (2004).
[CrossRef]

Chem. Phys. Lett. (1)

R. Stöckle, Y. Suh, V. Deckert, and R. Zenobi, "Nanoscale chemical analysis by tip-enhanced Raman spectroscopy," Chem. Phys. Lett. 318, 131-136 (2000).
[CrossRef]

IEEE Trans. Microwave Theory Tech. (1)

D. van der Weide, J. Murakowski, and F. Keilmann, "Gas-absorption spectroscopy with electronic Terahertz techniques," IEEE Trans. Microwave Theory Tech. 48, 740-743 (2000).
[CrossRef]

J. Microsc. (2)

R. Hillenbrand, B. Knoll, and F. Keilmann, "Pure optical contrast in scattering-type scanning near-field optical microscopy," J. Microsc. 202, 77-83 (2001).
[CrossRef] [PubMed]

T. Taubner, R. Hillenbrand, and F. Keilmann, "Performance of visible and mid-infrared scattering-type near-field optical microscopes," J. Microsc. 210, 311-314 (2003).
[CrossRef] [PubMed]

J. Opt. Soc. Am. B (1)

Nanoletters (3)

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nanoletters 4, 1669-1672 (2004).
[CrossRef]

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nanoletters 6, 1307-1310 (2006).
[CrossRef]

A. Huber, N. Ocelic, T. Taubner, and R. Hillenbrand, "Nanoscale resolved infrared probing of crystal structure and of plasmon-phonon coupling," Nanoletters 6, 774-778 (2006).
[CrossRef]

Nature (2)

R. Hillenbrand, T. Taubner, and F. Keilmann, "Phonon-enhanced light-matter interaction at the nanometre scale," Nature 418, 159-162 (2002).
[CrossRef] [PubMed]

B. Knoll and F. Keilmann, "Near-field probing of vibrational absorption for chemical microscopy," Nature 399, 134-137 (1999).
[CrossRef]

Nature Materials (1)

N. Ocelic and R. Hillenbrand, "Subwavelength-scale tailoring of surface phonon polaritons by focused ion-beam implementation," Nature Materials 3, 606-609 (2004).
[CrossRef] [PubMed]

Opt. Commun. (2)

B. Knoll and F. Keilmann, "Enhanced dielectric contrast in scattering-type scanning near-field optical microscopy," Opt. Commun. 182, 321-328 (2000).
[CrossRef]

A. Kulibekov, K. Allakhverdiev, D. Guseinova, E. Salaev, and O. Baran, "Optical absorption in GaSe under high-density ultrashort laser pulses," Opt. Commun. 239, 193-198 (2004).
[CrossRef]

Opt. Express (2)

Opt. Lett. (2)

Philos. Trans. R. Soc. London A (1)

F. Keilmann and R. Hillenbrand, "Near-field microscopy by elastic light scattering from a tip," Philos. Trans. R. Soc. London A 362, 787-805 (2004).
[CrossRef]

Phys. Rev. Lett. (1)

R. Hillenbrand and F. Keilmann, "Complex optical constants on a subwavelength scale," Phys. Rev. Lett. 85, 3029-3032 (2000).
[CrossRef] [PubMed]

Science (1)

F. Zenhausern, Y. Martin, and H. Wickramasinghe, "Scanning interferometric apertureless microscopy: optical imaging at 10 Angstrom resolution," Science 269, 1083-1085 (1995).
[CrossRef] [PubMed]

Supercond. Sci. Technol. (1)

A. Semenov, G. Goltsman, and R. Sobolewski, "Hot-electron effect in superconductors and its applications for radiation sensors," Supercond. Sci. Technol. 15, R1-R16 (2002).
[CrossRef]

Superlattices and Microstructures (1)

F. Formanek, Y. DeWilde, L. Aigouy, W.K. Kwok, L. Paulius, and Y. Chen, "Nanometer-scale probing of optical and thermal near-fields with an apertureless NSOM," Superlattices and Microstructures 35, 315-323 (2004).
[CrossRef]

Other (10)

A. Hartschuh, E. Sanchez, X. Xie, and L. Novotny, "High-resolution near-field Raman microscopy of singlewalled carbon nanotubes," Phys. Rev. Lett. 90, 095503-1-4 (2003).
[CrossRef] [PubMed]

T. Yasui, E. Saneyoshi, and T. Araki, "Asynchronous optical sampling terahertz time-domain spectroscopy for ultrahigh spectral resolution and rapid data acquisition," Appl. Phys. Lett. 87, 61101-1-3 (2005).
[CrossRef]

F. Keilmann, A. Schliesser, M. Brehm, and N. Ocelic, "Verfahren und Vorrichtung zur Abtastung von sich periodisch wiederholenden Ereignissen," German patent DE102005050151 (filed Oct. 10, 2005) (2006).

C. Fischer and M. W. Siegrist, "Mid-IR difference frequency generation," in Solid-state mid-infrared laser sources, I. Sorokina and K. Vodopyanov, eds., pp. 97-140 (Springer, Berlin, 2003).

T. Udem, R. Holzwarth, and T. W. H¨ansch, "Optical frequency metrology," Nature 416, 233-237 (2002).
[CrossRef] [PubMed]

D. van der Weide and F. Keilmann, "Coherent periodically pulsed radiation spectrometer," US patent 5748309 (filed Oct. 20, 1994) (1998).

M. Zimmermann, C. Gohle, R. Holzwarth, T. Udem, and T . Hünsch, "Optical clockwork with an offset-free difference-frequency comb: accuracy of sum- and difference-frequency generation," Opt. Lett. 29,310-312 (2004).
[CrossRef] [PubMed]

A. Schliesser, "Multiheterodyn-Spektroskopie mit Frequenzk¨ammen im mittleren Infrarot," Diplomarbeit, Technische Universität München (2005).

P. G. Gucciardi, G. Bachelier, and M. Allegrini, "Far-field background suppression in tip-modulated apertureless near-field optical microscopy," J. Appl. Phys. 99, 124309-1-9 (2006).
[CrossRef]

N. Ocelic, A. Huber, and R. Hillenbrand, "Pseudo-heterodyne detection for background-free near-field spectroscopy," Appl. Phys. Lett. 89, 101124-1-3 (2006).
[CrossRef]

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Figures (7)

Fig. 1.
Fig. 1.

Schematic optical path of spectroscopic mid-infrared near-field microscope, combining a coherent frequency-comb infrared spectrometer (comb-FTIR) with a scatteringtype scanning near-field optical microscope (s-SNOM). Two Ti:sapphire oscillators emit 10 fs near-infrared pulses (green beam paths) at slightly different repetition frequencies fr and fr +Δ whose coincidence is detected by a cross-correlation detector (CC). Two GaSe crystals generate broadband infrared beams (red beam paths) one of which is focused to and back-scattered from a cantilevered AFM tip, then superimposed with the other beam using a ZnSe beam combiner (BC). The infrared detector (DET) continuously records radiowave pulses that repeat at frequency Δ, each of them encoding a backscattered spectrum. The sample is raster-scanned.

Fig. 2.
Fig. 2.

(a) Normalized spectra of mid-infrared frequency-comb beam, determined with a classical FTIR spectrometer, for four different near-infrared beam incidence angles on a GaSe crystal oriented for type-I phase-matching; the total power decreases when tuning the spectra towards higher frequencies. (b) Comb-FTIR “input” spectrum for illuminating the near-field microscope, measured with a flat mirror inserted between BC and s-SNOM in Fig. 1, by recording a single radiowave transient interferogram and subsequent Fourier transformation.

Fig. 3.
Fig. 3.

Infrared s-SNOM images (4×3.5 µm2, recorded in 2 min.) of partly Au-covered SiC. The topography shows the 20 nm Au film on the left side, and some dust particles. The infrared images are obtained at 2Ω demodulation of the detector signal with illumination either by monochromatic CO2 laser at 932 cm-1, or spectrally-integrated broadband beam 1 spanning 800-1100 cm-1. The arrow depicts the direction of the incident beam (for explanation of dashed line and color series see Fig. 5).

Fig. 4.
Fig. 4.

Comb-FTIR radiowave transients of tip scattering; (red) trigger pulse from cross correlation, (black) infrared interferograms, single, 10 and 100 averaged, respectively, from top to bottom.

Fig. 5.
Fig. 5.

Results of an infrared-spectroscopic s-SNOM line scan taken in 20 min, along the 4 µm long dashed line in Fig. 3. Three complex (amplitude and phase) spectra are evaluated and colour coded as marked in Fig. 3, for each of 20 sequential tip positions separated by 200 nm. The upper panel shows the direct scattering spectrum σ 0 which transforms gradually from the initial position on Au (green) to the final on SiC (yellow). The middle and lower panels, respectively, show demodulated spectra of first and second order, σ 1 and σ 2 that change abruptly at the material boundary, and are dominated by the near-field interaction between tip and sample material.

Fig. 6.
Fig. 6.

S-SNOM amplitude spectra (slightly smoothed) vs approach of SiC sample, with tip-sample distances z indicated in the inset. The near-field resonance in s 1 appears only at tip-sample distances z<100 nm, as to be expected for the limited reach of near-field interaction.

Fig. 7.
Fig. 7.

Normalized scattering contrast spectrum, in amplitude and phase (full curves, smoothed), of σ 1 response of SiC relative to Au, obtained as average (data points) over σ 1 spectra in Fig. 5. As Au is dispersionless in the mid infrared, this relative spectrum largely depicts the near-field phonon-resonant interaction between tip and SiC.

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