Abstract

We demonstrate a scattering-type scanning near-field optical microscope (s-SNOM) with broadband THz illumination. A cantilevered W tip is used in tapping AFM mode. The direct scattering spectrum is obtained and optimized by asynchronous optical sampling (ASOPS), while near-field scattering is observed by using a space-domain delay stage and harmonic demodulation of the detector signal. True near-field interaction is determined from the approach behavior of the tip to Au samples. Scattering spectra of differently doped Si are presented.

© 2008 Optical Society of America

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2007 (5)

B. Gompf, N. Gebert, H. Heer, and M. Dressel, "Polarization contrast terahertz-near-field imaging of anisotropic conductors," Appl. Phys. Lett. 90, 82104 (2007).
[CrossRef]

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[CrossRef]

W. L. Chan, J. Deibel, and D. M. Mittleman, "Imaging with terahertz radiation," Rep. Prog. Phys. 70, 1325-1379 (2007).
[CrossRef]

A. Cvitkovic, N. Ocelic, and R. Hillenbrand, "Analytical model for quantitative prediction of material contrasts in scattering-type near-field optical microscopy," Opt. Express 15, 8550-8565 (2007).
[CrossRef] [PubMed]

2006 (5)

M. Brehm, A. Schliesser, and F. Keilmann, "Spectroscopic near-field microscopy using frequency combs in the mid-infrared," Opt. Express 14, 11222-11233 (2006).
[CrossRef] [PubMed]

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]

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

F. F. Buersgens, H. T. Chen, and R. Kersting, "Terahertz microscopy of charge carriers in semiconductors," Appl. Phys. Lett. 88, 112115 (2006).
[CrossRef]

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

2005 (1)

P. C. M. Planken, C. E. W. M. Rijmenam, and R. N. Schouten, "Opto-electronic pulsed THz systems," Semicond. Sci. Technol. 20, 121-127 (2005).
[CrossRef]

2004 (5)

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nano Lett. 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]

U. Schade and K. Holldack, "THz near-field imaging employing synchrotron radiation," Appl. Phys. Lett. 84, 1422-1424 (2004).
[CrossRef]

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

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

2003 (3)

T. Kiwa, M. Tonouchi, M. Yamashita, and K. Kawase, "Laser terahertz-emission microscope for inspecting electronic faults in integrated circuits," Opt. Lett. 28, 2058-2060 (2003).
[CrossRef] [PubMed]

H. T. Chen, R. Kersting, and G. C. Cho, "THz imaging with nanometer resolution," Appl. Phys. Lett. 83, 3009-3011 (2003).
[CrossRef]

M. B. Raschke, and C. Lienau, "Apertureless near-field optical microscopy: tip-sample coupling in elastic light scattering," Appl. Phys. Lett. 83, 5089-5091 (2003).
[CrossRef]

2002 (3)

N. C. J. v. d. Valk, and P. C. M. Planken, "Electro-optic detection of subwavelength terahertz spot sizes in the near field of a metal tip," Appl. Phys. Lett. 81, 1558-1560 (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 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]

2000 (3)

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]

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]

B. Knoll and F. Keilmann, "Electromagnetic fields in the cutoff regime of tapered metallic waveguides," Opt. Commun. 162, 177-181 (1999).
[CrossRef]

1998 (1)

S. Hunsche and M. Koch, "THz near-field imaging," Opt. Commun. 150, 22-26 (1998).
[CrossRef]

1997 (1)

B. Knoll, F. Keilmann, A. Kramer, and R. Guckenberger, "Contrast of microwave near-field microscopy," Appl. Phys. Lett. 70, 2667-2669 (1997).
[CrossRef]

1996 (1)

F. Keilmann, D. W. v. d. Weide, T. Eickelkamp, R. Merz, and D. Stöckle, "Extreme sub-wavelength resolution with a scanning radio-frequency transmission microscope," Opt. Commun. 129, 15-18 (1996).
[CrossRef]

1994 (2)

F. Zenhausern, M. P. O’Boyle, and H. K. Wickramasinghe, "Apertureless near-field optical microscope," Appl. Phys. Lett. 65, 1623-1625 (1994).
[CrossRef]

F. Keilmann, "FIR Microscopy," Infrared Phys. Technol. 36, 217-224 (1994).
[CrossRef]

1993 (1)

R. Merz, F. Keilmann, R. J. Haug, and K. Ploog, "Nonequilibrium edge-state transport resolved by far-infrared microscopy," Phys. Rev. Lett. 70, 651-653 (1993).
[CrossRef] [PubMed]

1989 (1)

M. Fee, S. Chu, and T. W. Hänsch, "Scanning electromagnetic transmission line microscope with sub-wavelength resolution," Opt. Commun. 69, 219-224 (1989).
[CrossRef]

1987 (1)

1970 (1)

L. M. Matarrese and K. M. Evenson, "Improved coupling to infrared whisker diodes by use of antenna theory," Appl. Phys. Lett. 17, 8-10 (1970).
[CrossRef]

Barbey, N.

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

Bartels, A.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[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]

Boccara, A. C.

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

Brehm, M.

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

M. Brehm, A. Schliesser, and F. Keilmann, "Spectroscopic near-field microscopy using frequency combs in the mid-infrared," Opt. Express 14, 11222-11233 (2006).
[CrossRef] [PubMed]

Buersgens, F. F.

F. F. Buersgens, H. T. Chen, and R. Kersting, "Terahertz microscopy of charge carriers in semiconductors," Appl. Phys. Lett. 88, 112115 (2006).
[CrossRef]

Cerna, R.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[CrossRef]

Chan, W. L.

W. L. Chan, J. Deibel, and D. M. Mittleman, "Imaging with terahertz radiation," Rep. Prog. Phys. 70, 1325-1379 (2007).
[CrossRef]

Chen, H. T.

F. F. Buersgens, H. T. Chen, and R. Kersting, "Terahertz microscopy of charge carriers in semiconductors," Appl. Phys. Lett. 88, 112115 (2006).
[CrossRef]

H. T. Chen, R. Kersting, and G. C. Cho, "THz imaging with nanometer resolution," Appl. Phys. Lett. 83, 3009-3011 (2003).
[CrossRef]

Cho, G. C.

H. T. Chen, R. Kersting, and G. C. Cho, "THz imaging with nanometer resolution," Appl. Phys. Lett. 83, 3009-3011 (2003).
[CrossRef]

Chu, S.

M. Fee, S. Chu, and T. W. Hänsch, "Scanning electromagnetic transmission line microscope with sub-wavelength resolution," Opt. Commun. 69, 219-224 (1989).
[CrossRef]

Cvitkovic, A.

Deibel, J.

W. L. Chan, J. Deibel, and D. M. Mittleman, "Imaging with terahertz radiation," Rep. Prog. Phys. 70, 1325-1379 (2007).
[CrossRef]

Dekorsy, T.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[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]

Dressel, M.

B. Gompf, N. Gebert, H. Heer, and M. Dressel, "Polarization contrast terahertz-near-field imaging of anisotropic conductors," Appl. Phys. Lett. 90, 82104 (2007).
[CrossRef]

Dreyhaupt, A.

Elzinga, P. A.

Evenson, K. M.

L. M. Matarrese and K. M. Evenson, "Improved coupling to infrared whisker diodes by use of antenna theory," Appl. Phys. Lett. 17, 8-10 (1970).
[CrossRef]

Fee, M.

M. Fee, S. Chu, and T. W. Hänsch, "Scanning electromagnetic transmission line microscope with sub-wavelength resolution," Opt. Commun. 69, 219-224 (1989).
[CrossRef]

Gebert, N.

B. Gompf, N. Gebert, H. Heer, and M. Dressel, "Polarization contrast terahertz-near-field imaging of anisotropic conductors," Appl. Phys. Lett. 90, 82104 (2007).
[CrossRef]

Gompf, B.

B. Gompf, N. Gebert, H. Heer, and M. Dressel, "Polarization contrast terahertz-near-field imaging of anisotropic conductors," Appl. Phys. Lett. 90, 82104 (2007).
[CrossRef]

Gresillon, S.

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

Guckenberger, R.

B. Knoll, F. Keilmann, A. Kramer, and R. Guckenberger, "Contrast of microwave near-field microscopy," Appl. Phys. Lett. 70, 2667-2669 (1997).
[CrossRef]

Hänsch, T. W.

M. Fee, S. Chu, and T. W. Hänsch, "Scanning electromagnetic transmission line microscope with sub-wavelength resolution," Opt. Commun. 69, 219-224 (1989).
[CrossRef]

Haug, R. J.

R. Merz, F. Keilmann, R. J. Haug, and K. Ploog, "Nonequilibrium edge-state transport resolved by far-infrared microscopy," Phys. Rev. Lett. 70, 651-653 (1993).
[CrossRef] [PubMed]

Heer, H.

B. Gompf, N. Gebert, H. Heer, and M. Dressel, "Polarization contrast terahertz-near-field imaging of anisotropic conductors," Appl. Phys. Lett. 90, 82104 (2007).
[CrossRef]

Helm, M.

Hillenbrand, R.

A. Cvitkovic, N. Ocelic, and R. Hillenbrand, "Analytical model for quantitative prediction of material contrasts in scattering-type near-field optical microscopy," Opt. Express 15, 8550-8565 (2007).
[CrossRef] [PubMed]

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nano Lett. 6, 1307-1310 (2006).
[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," Nano Lett. 4, 1669-1672 (2004).
[CrossRef]

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

N. Ocelic and R. Hillenbrand, "Subwavelength-scale tailoring of surface phonon polaritons by focused ion-beam implantation," Nature Mater. 3, 606-609 (2004).
[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 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 and F. Keilmann, "Complex optical constants on a subwavelength scale," Phys. Rev. Lett. 85, 3029-3032 (2000).
[CrossRef] [PubMed]

Holldack, K.

U. Schade and K. Holldack, "THz near-field imaging employing synchrotron radiation," Appl. Phys. Lett. 84, 1422-1424 (2004).
[CrossRef]

Huber, A. J.

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

Hudert, F.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[CrossRef]

Hunsche, S.

S. Hunsche and M. Koch, "THz near-field imaging," Opt. Commun. 150, 22-26 (1998).
[CrossRef]

Janke, C.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[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]

Kawase, K.

Kazantsev, D.

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

Keilmann, F.

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

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

M. Brehm, A. Schliesser, and F. Keilmann, "Spectroscopic near-field microscopy using frequency combs in the mid-infrared," Opt. Express 14, 11222-11233 (2006).
[CrossRef] [PubMed]

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nano Lett. 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, Ser. A 362, 787-805 (2004).
[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 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 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]

B. Knoll and F. Keilmann, "Electromagnetic fields in the cutoff regime of tapered metallic waveguides," Opt. Commun. 162, 177-181 (1999).
[CrossRef]

B. Knoll, F. Keilmann, A. Kramer, and R. Guckenberger, "Contrast of microwave near-field microscopy," Appl. Phys. Lett. 70, 2667-2669 (1997).
[CrossRef]

F. Keilmann, D. W. v. d. Weide, T. Eickelkamp, R. Merz, and D. Stöckle, "Extreme sub-wavelength resolution with a scanning radio-frequency transmission microscope," Opt. Commun. 129, 15-18 (1996).
[CrossRef]

F. Keilmann, "FIR Microscopy," Infrared Phys. Technol. 36, 217-224 (1994).
[CrossRef]

R. Merz, F. Keilmann, R. J. Haug, and K. Ploog, "Nonequilibrium edge-state transport resolved by far-infrared microscopy," Phys. Rev. Lett. 70, 651-653 (1993).
[CrossRef] [PubMed]

Kersting, R.

F. F. Buersgens, H. T. Chen, and R. Kersting, "Terahertz microscopy of charge carriers in semiconductors," Appl. Phys. Lett. 88, 112115 (2006).
[CrossRef]

H. T. Chen, R. Kersting, and G. C. Cho, "THz imaging with nanometer resolution," Appl. Phys. Lett. 83, 3009-3011 (2003).
[CrossRef]

Kistner, C.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[CrossRef]

Kiwa, T.

Kneisler, R. J.

Knoll, B.

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]

B. Knoll and F. Keilmann, "Electromagnetic fields in the cutoff regime of tapered metallic waveguides," Opt. Commun. 162, 177-181 (1999).
[CrossRef]

B. Knoll, F. Keilmann, A. Kramer, and R. Guckenberger, "Contrast of microwave near-field microscopy," Appl. Phys. Lett. 70, 2667-2669 (1997).
[CrossRef]

Koch, M.

S. Hunsche and M. Koch, "THz near-field imaging," Opt. Commun. 150, 22-26 (1998).
[CrossRef]

Kramer, A.

B. Knoll, F. Keilmann, A. Kramer, and R. Guckenberger, "Contrast of microwave near-field microscopy," Appl. Phys. Lett. 70, 2667-2669 (1997).
[CrossRef]

Lecaque, R.

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

Lienau, C.

M. B. Raschke, and C. Lienau, "Apertureless near-field optical microscopy: tip-sample coupling in elastic light scattering," Appl. Phys. Lett. 83, 5089-5091 (2003).
[CrossRef]

Lytle, F. E.

Matarrese, L. M.

L. M. Matarrese and K. M. Evenson, "Improved coupling to infrared whisker diodes by use of antenna theory," Appl. Phys. Lett. 17, 8-10 (1970).
[CrossRef]

Merz, R.

R. Merz, F. Keilmann, R. J. Haug, and K. Ploog, "Nonequilibrium edge-state transport resolved by far-infrared microscopy," Phys. Rev. Lett. 70, 651-653 (1993).
[CrossRef] [PubMed]

Mittleman, D. M.

W. L. Chan, J. Deibel, and D. M. Mittleman, "Imaging with terahertz radiation," Rep. Prog. Phys. 70, 1325-1379 (2007).
[CrossRef]

O’Boyle, M. P.

F. Zenhausern, M. P. O’Boyle, and H. K. Wickramasinghe, "Apertureless near-field optical microscope," Appl. Phys. Lett. 65, 1623-1625 (1994).
[CrossRef]

Ocelic, N.

A. Cvitkovic, N. Ocelic, and R. Hillenbrand, "Analytical model for quantitative prediction of material contrasts in scattering-type near-field optical microscopy," Opt. Express 15, 8550-8565 (2007).
[CrossRef] [PubMed]

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

Peretti, R.

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

Planken, P. C. M.

P. C. M. Planken, C. E. W. M. Rijmenam, and R. N. Schouten, "Opto-electronic pulsed THz systems," Semicond. Sci. Technol. 20, 121-127 (2005).
[CrossRef]

Ploog, K.

R. Merz, F. Keilmann, R. J. Haug, and K. Ploog, "Nonequilibrium edge-state transport resolved by far-infrared microscopy," Phys. Rev. Lett. 70, 651-653 (1993).
[CrossRef] [PubMed]

Raschke, M. B.

M. B. Raschke, and C. Lienau, "Apertureless near-field optical microscopy: tip-sample coupling in elastic light scattering," Appl. Phys. Lett. 83, 5089-5091 (2003).
[CrossRef]

Rijmenam, C. E. W. M.

P. C. M. Planken, C. E. W. M. Rijmenam, and R. N. Schouten, "Opto-electronic pulsed THz systems," Semicond. Sci. Technol. 20, 121-127 (2005).
[CrossRef]

Rivoal, J. C.

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

Schade, U.

U. Schade and K. Holldack, "THz near-field imaging employing synchrotron radiation," Appl. Phys. Lett. 84, 1422-1424 (2004).
[CrossRef]

Schliesser, A.

Schouten, R. N.

P. C. M. Planken, C. E. W. M. Rijmenam, and R. N. Schouten, "Opto-electronic pulsed THz systems," Semicond. Sci. Technol. 20, 121-127 (2005).
[CrossRef]

Taubner, T.

M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann, "Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution," Nano Lett. 6, 1307-1310 (2006).
[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," Nano Lett. 4, 1669-1672 (2004).
[CrossRef]

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

Thoma, A.

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[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]

Tonouchi, M.

Wickramasinghe, H. K.

F. Zenhausern, M. P. O’Boyle, and H. K. Wickramasinghe, "Apertureless near-field optical microscope," Appl. Phys. Lett. 65, 1623-1625 (1994).
[CrossRef]

Winnerl, S.

Wittborn, J.

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

Yamashita, M.

Zenhausern, F.

F. Zenhausern, M. P. O’Boyle, and H. K. Wickramasinghe, "Apertureless near-field optical microscope," Appl. Phys. Lett. 65, 1623-1625 (1994).
[CrossRef]

Adv. Mater. (1)

A. J. Huber, D. Kazantsev, F. Keilmann, J. Wittborn, and R. Hillenbrand, "Simultaneous infrared material recognition and conductivity mapping by nanoscale near-field microscopy," Adv. Mater. 19, 2209-2213 (2007).
[CrossRef]

Appl. Opt. (1)

Appl. Phys. Lett. (12)

N. C. J. v. d. Valk, and P. C. M. Planken, "Electro-optic detection of subwavelength terahertz spot sizes in the near field of a metal tip," Appl. Phys. Lett. 81, 1558-1560 (2002).
[CrossRef]

H. T. Chen, R. Kersting, and G. C. Cho, "THz imaging with nanometer resolution," Appl. Phys. Lett. 83, 3009-3011 (2003).
[CrossRef]

F. F. Buersgens, H. T. Chen, and R. Kersting, "Terahertz microscopy of charge carriers in semiconductors," Appl. Phys. Lett. 88, 112115 (2006).
[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]

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]

B. Gompf, N. Gebert, H. Heer, and M. Dressel, "Polarization contrast terahertz-near-field imaging of anisotropic conductors," Appl. Phys. Lett. 90, 82104 (2007).
[CrossRef]

U. Schade and K. Holldack, "THz near-field imaging employing synchrotron radiation," Appl. Phys. Lett. 84, 1422-1424 (2004).
[CrossRef]

B. Knoll, F. Keilmann, A. Kramer, and R. Guckenberger, "Contrast of microwave near-field microscopy," Appl. Phys. Lett. 70, 2667-2669 (1997).
[CrossRef]

F. Zenhausern, M. P. O’Boyle, and H. K. Wickramasinghe, "Apertureless near-field optical microscope," Appl. Phys. Lett. 65, 1623-1625 (1994).
[CrossRef]

L. M. Matarrese and K. M. Evenson, "Improved coupling to infrared whisker diodes by use of antenna theory," Appl. Phys. Lett. 17, 8-10 (1970).
[CrossRef]

M. B. Raschke, and C. Lienau, "Apertureless near-field optical microscopy: tip-sample coupling in elastic light scattering," Appl. Phys. Lett. 83, 5089-5091 (2003).
[CrossRef]

Infrared Phys. Technol. (1)

F. Keilmann, "FIR Microscopy," Infrared Phys. Technol. 36, 217-224 (1994).
[CrossRef]

Nano Lett. (2)

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

T. Taubner, F. Keilmann, and R. Hillenbrand, "Nanomechanical resonance tuning and phase effects in optical near-field interaction," Nano Lett. 4, 1669-1672 (2004).
[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 Mater. (1)

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

Opt. Commun. (6)

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

R. Lecaque, S. Gresillon, N. Barbey, R. Peretti, J. C. Rivoal, and A. C. Boccara, "THz near-field optical imaging by a local source," Opt. Commun. 262, 125-127 (2006).
[CrossRef]

F. Keilmann, D. W. v. d. Weide, T. Eickelkamp, R. Merz, and D. Stöckle, "Extreme sub-wavelength resolution with a scanning radio-frequency transmission microscope," Opt. Commun. 129, 15-18 (1996).
[CrossRef]

M. Fee, S. Chu, and T. W. Hänsch, "Scanning electromagnetic transmission line microscope with sub-wavelength resolution," Opt. Commun. 69, 219-224 (1989).
[CrossRef]

S. Hunsche and M. Koch, "THz near-field imaging," Opt. Commun. 150, 22-26 (1998).
[CrossRef]

B. Knoll and F. Keilmann, "Electromagnetic fields in the cutoff regime of tapered metallic waveguides," Opt. Commun. 162, 177-181 (1999).
[CrossRef]

Opt. Express (3)

Opt. Lett. (1)

Phys. Rev. Lett. (2)

R. Merz, F. Keilmann, R. J. Haug, and K. Ploog, "Nonequilibrium edge-state transport resolved by far-infrared microscopy," Phys. Rev. Lett. 70, 651-653 (1993).
[CrossRef] [PubMed]

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

Rep. Prog. Phys. (1)

W. L. Chan, J. Deibel, and D. M. Mittleman, "Imaging with terahertz radiation," Rep. Prog. Phys. 70, 1325-1379 (2007).
[CrossRef]

Rev. Sci. Instrum. (1)

A. Bartels, R. Cerna, C. Kistner, A. Thoma, F. Hudert, C. Janke, and T. Dekorsy, "Ultrafast time-domain spectroscopy based on high-speed asynchronuous optical sampling," Rev. Sci. Instrum. 78, 351071-351078 (2007).
[CrossRef]

Semicond. Sci. Technol. (1)

P. C. M. Planken, C. E. W. M. Rijmenam, and R. N. Schouten, "Opto-electronic pulsed THz systems," Semicond. Sci. Technol. 20, 121-127 (2005).
[CrossRef]

Ser. A (1)

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

Other (9)

S. M. Anlage, D. E. Steinhauer, B. J. Feenstra, C. P. Vlahacos, and F. C. Wellstood, "Near-field microwave microscopy of materials properties," in Microwave Superconductivity, H. Weinstock, and M. Nisenoff, eds., (Kluwer, Amsterdam, 2001), pp. 239-269.

H. Kuzmany, Solid-State Spectroscopy (Springer, Berlin, 1998).

F. Keilmann, "Scanning tip for optical radiation," in U.S. Patent 4,994,818 (1988),

T. Yasui, Y. Kabetani, E. Saneyoshi, S. Yokoyama, and T. Araki, "Terahertz frequency comb by multifrequency heterodyning photoconductive detection for high-accuracy, high-resolution terahertz spectroscopy," Appl. Phys. Lett. 88, 241104 (2006).
[CrossRef]

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, 61101-61103 (2005).
[CrossRef]

S. Schneider, J. Seidel, S. Grafström, L. M. Eng, S. Winnerl, D. Stehr, and H. Helm, "Impact of optical in-plane anisotropy on near-field phonon polariton spectroscopy," Appl. Phys. Lett. 90, 143101-143103 (2007).
[CrossRef]

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

F. Keilmann and R. Hillenbrand, "Mirror optic for near-field optical measurements," patent DE 102006002461 filed 18.1.2006 (US filed 16.1.2007, 2006).

M. Brehm, "Infrarot-Mikrospektroskopie mit einem Nahfeldmikroskop," Dissertation, Fakultät für Physik, Technische Universität, München, p. 128 (2006).

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Figures (6)

Fig. 1.
Fig. 1.

Optical layout of spectroscopic THz s-SNOM. A common paraboloid mirror m1 serves for both focusing to the tip and for recollimating THz radiation scattered by about 90° sideways.[45] The THz beam is generated by driving a GaAs emitter with Ti:sapphire laser pulses, and is detected by a standard e.o. setup. A second Ti:sapphire laser (dashed frame) serves to provide a purely time-domain delay, resulting in rapid sequence of spectra. This ASOPS mode is used for s-SNOM alignment. THz s-SNOM operation proceeds by using space-domain delay, involving the delay stage shown but not the second laser.

Fig. 2.
Fig. 2.

SEM image of hand-made cantilevered s-SNOM probe for tapping-mode operation, made of 65 µm W wire by bending and electrochemically etching to a tip radius below 500 nm.

Fig. 3.
Fig. 3.

Experimental THz s-SNOM spectra of Au using the space-domain delay method (no averaging). The input spectrum is obtained by placing a mirror pair before the focusing paraboloid. This and the direct scattering spectra are taken at 5x speed. The first (s1) and second-order demodulated scattering spectra (s2) are shown. In all spectra (including those in Figs. 4,5) the data points are from measurement, the curves are obtained by weighted smoothing.

Fig. 4.
Fig. 4.

Approach curves of demodulated THz signals using a W tip (radius 300 nm) on a flat Au sample (three curves averaged). The tapping amplitude reduces when contact is made. The THz field amplitude decays at a characteristic distance from the sample, giving the range of near-field interaction which is connected to the attainable spatial resolution.

Fig. 5.
Fig. 5.

Experimental THz s-SNOM amplitude-contrast spectra (s2) of doped Si, normalized to Au (experimental dots; the dashed curves are guides to the eye).

Fig. 6.
Fig. 6.

Theoretical THz s-SNOM amplitude-contrast spectra of doped Si normalized to Au, calculated by the point-dipole/mirror-dipole model for different free electron densities ne.

Equations (1)

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se i φ ( 1 + r ) 2 α ( 1 α β ( 16 π ( a + z ) 3 ) ) ,

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