Abstract

We demonstrate bio-medical imaging using a Terahertz quantum cascade laser. This new optoelectronic source of coherent Terahertz radiation allows building a compact imaging system with a large dynamic range and high spatial resolution. We obtain images of a rat brain section at 3.4 THz. Distinct regions of brain tissue rich in fat, proteins, and fluid-filled cavities are resolved showing the high contrast of Terahertz radiation for biological tissue. These results suggest that continuous-wave Terahertz imaging with a carefully chosen wavelength can provide valuable data on samples of biological origin; these data appear complementary to those obtained from white-light images.

© 2004 Optical Society of America

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  1. D. M. Mittleman, R. H. Jacobsen, and M. C. Nuss, �??T-ray imaging,�?? IEEE J. Sel. Top. Quantum Electron. 2, 679-692 (1992).
  2. S. Hunsche, M. Koch, I. Brener, and M. C. Nuss, �??THz near-field imaging,�?? Opt. Commun. 150, 22-26 (1998).
    [CrossRef]
  3. E. Pickwell, B. E. Cole, A. J. Fitzgerald, M. Pepper, and V. P. Wallace, �??In vivo study of human skin using pulsed terahertz radiation,�?? Phys. Med. Biol. 49, 1595-1607 (2004).
    [CrossRef] [PubMed]
  4. K. J. Siebert, T. Loffler, H. Quast, M. Thomson, T. Bauer, R. Leonhardt, S. Czasch, H. G. Roskos, �??All-optoelectronic continuous wave THz imaging for biomedical applications,�?? Phys. Med. Biol. 47, 3743-3748 (2002).
    [CrossRef] [PubMed]
  5. P. Knobloch, C. Schildknecht, T. Kleine-Ostmann, M. Koch, S. Hoffmann, E. Rehberg, M. Sperling, K. Donhuijsen, G. Hein, and K. Pierz, �??Medical THz imaging: an investigation of histo-pathological samples,�?? Phys. Med. Biol. 47, 3875-3884 (2002).
    [CrossRef] [PubMed]
  6. T. Kleine-Ostmann, P. Knobloch, M. Koch, S. Hoffmann, M. Breede, M. Hofmann, G. Hein, K. Pierz, M. Sperling, K. Donhuijsen, �??Continuous-wave THz imaging,�?? Electron. Lett. 37, 1461-1463 (2001).
    [CrossRef]
  7. J. Darmo, T. Müller, G. Straser, K. Unterrainer, and G. Tempea, �??Terahertz emitter with intergrated semiconductor Bragg mirror,�?? Electron. Lett. 39, 460-462 (2003).
    [CrossRef]
  8. K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, �??Terahertz photomixing with diode lasers in low-temperature-grown GaAs,�?? Appl. Physl. Lett. 67, 3844-3846 (1995).
    [CrossRef]
  9. E. R. Brown, K. A. McIntosh, K. B. Nichols, and C. L. Dennis, �??Photomixing up to 3.8 THz in low-temperature-grown GaAs,�?? Appl. Phys. Lett. 66, 285-287 (1995).
    [CrossRef]
  10. S. Verghese, K. A. McIntosh, S. M. Duffy, and E. K. Duerr, �??Continuous-wave Terahertz generation using photomixers,�?? in Terahertz Sources and Systems, R.E. Miler et al,. eds. (Kluwer Academic Publishers, Netherlands, 2001) pp. 145-165.
  11. P. Gu, F. Chang, M. Tani, K. Sakai, and C.-L. Pan, �??Generation of coherent cw-Terahertz radiation using a tunable dual-wavelength external cavity laser diode,�?? Jpn. J. Appl. Phys. 38, L1246-L1248 (1999).
    [CrossRef]
  12. M. Rochat, L. Ajili, H. Willenberg, J. Faist, H. Beere, G. Davies, E. Linfield, and D. Ritchie, �??Low-threshold Terahertz quantum-cascade lasers,�?? Appl. Phys. Lett. 81, 1381-1383 (2002).
    [CrossRef]
  13. R. Köhler, A. Terdicucci, F. Beltram, H.E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, S. S. Dhillon, and C. Sirtori, �??High-performance continuous-wave operation of superlattice Terahertz quantum-cascade lasers,�?? Appl. Phys. Lett. 82, 1518-1520 (2003).
    [CrossRef]
  14. G. Scalari, L. Ajili, J. Faist, H. Beere, E. Linfield, D. Ritchie, and G. Davies, �??Far-infrared (λ=78 µm) bound-to-continuum quantum-cascade lasers operating up to 90 K,�?? Appl. Phys. Lett. 82, 3165-3167 (2003).
    [CrossRef]
  15. B.S. Williams, H. Callebaut, S. Kumar, Q. Hu, and J. L. Reno, �??3.4-THz quantum cascade laser based on longitudinal-optical-phonon scattering for depopulation,�?? Appl. Phys. Lett. 82, 1015-1017 (2003).
    [CrossRef]
  16. B.S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, �??Terahertz quantum cascade laser at λ=100 µm using metal waveguide for mode confinement,�?? Appl. Phys. Lett. 83, 2124-2126 (2003).
    [CrossRef]
  17. M. Graf, G. Scalari, D. Hofstetter, J. Faist, H. Beere, E. Linfield, D. Ritchie, and G. Davies, �??Terahertz range quantum well infrared photodetector,�?? Appl. Phys. Lett. 84, 475-477 (2004).
    [CrossRef]
  18. M.F. Schocke, R. Waldner, Z. Puschban, C. Kolbitsch, K. Seppi, C. Scherfler, C. Kremser, F. Zschiegner, S. Felber, W. Poewe, G.K. Wenning, �??Vivo Magnetic Resonance Imaging of Embryonic Neural Grafts in a Rat Model of Striatonigral Degeneration (Multiple System Atrophy),�?? Neuroimage 12, 209-218 (2000).
    [CrossRef] [PubMed]

Appl. Phys. Lett. (7)

E. R. Brown, K. A. McIntosh, K. B. Nichols, and C. L. Dennis, �??Photomixing up to 3.8 THz in low-temperature-grown GaAs,�?? Appl. Phys. Lett. 66, 285-287 (1995).
[CrossRef]

M. Rochat, L. Ajili, H. Willenberg, J. Faist, H. Beere, G. Davies, E. Linfield, and D. Ritchie, �??Low-threshold Terahertz quantum-cascade lasers,�?? Appl. Phys. Lett. 81, 1381-1383 (2002).
[CrossRef]

R. Köhler, A. Terdicucci, F. Beltram, H.E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, S. S. Dhillon, and C. Sirtori, �??High-performance continuous-wave operation of superlattice Terahertz quantum-cascade lasers,�?? Appl. Phys. Lett. 82, 1518-1520 (2003).
[CrossRef]

G. Scalari, L. Ajili, J. Faist, H. Beere, E. Linfield, D. Ritchie, and G. Davies, �??Far-infrared (λ=78 µm) bound-to-continuum quantum-cascade lasers operating up to 90 K,�?? Appl. Phys. Lett. 82, 3165-3167 (2003).
[CrossRef]

B.S. Williams, H. Callebaut, S. Kumar, Q. Hu, and J. L. Reno, �??3.4-THz quantum cascade laser based on longitudinal-optical-phonon scattering for depopulation,�?? Appl. Phys. Lett. 82, 1015-1017 (2003).
[CrossRef]

B.S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, �??Terahertz quantum cascade laser at λ=100 µm using metal waveguide for mode confinement,�?? Appl. Phys. Lett. 83, 2124-2126 (2003).
[CrossRef]

M. Graf, G. Scalari, D. Hofstetter, J. Faist, H. Beere, E. Linfield, D. Ritchie, and G. Davies, �??Terahertz range quantum well infrared photodetector,�?? Appl. Phys. Lett. 84, 475-477 (2004).
[CrossRef]

Appl. Physl. Lett. (1)

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, �??Terahertz photomixing with diode lasers in low-temperature-grown GaAs,�?? Appl. Physl. Lett. 67, 3844-3846 (1995).
[CrossRef]

Electron. Lett. (2)

T. Kleine-Ostmann, P. Knobloch, M. Koch, S. Hoffmann, M. Breede, M. Hofmann, G. Hein, K. Pierz, M. Sperling, K. Donhuijsen, �??Continuous-wave THz imaging,�?? Electron. Lett. 37, 1461-1463 (2001).
[CrossRef]

J. Darmo, T. Müller, G. Straser, K. Unterrainer, and G. Tempea, �??Terahertz emitter with intergrated semiconductor Bragg mirror,�?? Electron. Lett. 39, 460-462 (2003).
[CrossRef]

IEEE J. Sel. Top. Quantum Electron. (1)

D. M. Mittleman, R. H. Jacobsen, and M. C. Nuss, �??T-ray imaging,�?? IEEE J. Sel. Top. Quantum Electron. 2, 679-692 (1992).

Jpn. J. Appl. Phys. (1)

P. Gu, F. Chang, M. Tani, K. Sakai, and C.-L. Pan, �??Generation of coherent cw-Terahertz radiation using a tunable dual-wavelength external cavity laser diode,�?? Jpn. J. Appl. Phys. 38, L1246-L1248 (1999).
[CrossRef]

Neuroimage (1)

M.F. Schocke, R. Waldner, Z. Puschban, C. Kolbitsch, K. Seppi, C. Scherfler, C. Kremser, F. Zschiegner, S. Felber, W. Poewe, G.K. Wenning, �??Vivo Magnetic Resonance Imaging of Embryonic Neural Grafts in a Rat Model of Striatonigral Degeneration (Multiple System Atrophy),�?? Neuroimage 12, 209-218 (2000).
[CrossRef] [PubMed]

Opt. Commun. (1)

S. Hunsche, M. Koch, I. Brener, and M. C. Nuss, �??THz near-field imaging,�?? Opt. Commun. 150, 22-26 (1998).
[CrossRef]

Phys. Med. Biol. (3)

E. Pickwell, B. E. Cole, A. J. Fitzgerald, M. Pepper, and V. P. Wallace, �??In vivo study of human skin using pulsed terahertz radiation,�?? Phys. Med. Biol. 49, 1595-1607 (2004).
[CrossRef] [PubMed]

K. J. Siebert, T. Loffler, H. Quast, M. Thomson, T. Bauer, R. Leonhardt, S. Czasch, H. G. Roskos, �??All-optoelectronic continuous wave THz imaging for biomedical applications,�?? Phys. Med. Biol. 47, 3743-3748 (2002).
[CrossRef] [PubMed]

P. Knobloch, C. Schildknecht, T. Kleine-Ostmann, M. Koch, S. Hoffmann, E. Rehberg, M. Sperling, K. Donhuijsen, G. Hein, and K. Pierz, �??Medical THz imaging: an investigation of histo-pathological samples,�?? Phys. Med. Biol. 47, 3875-3884 (2002).
[CrossRef] [PubMed]

Terahertz Sources and Systems (1)

S. Verghese, K. A. McIntosh, S. M. Duffy, and E. K. Duerr, �??Continuous-wave Terahertz generation using photomixers,�?? in Terahertz Sources and Systems, R.E. Miler et al,. eds. (Kluwer Academic Publishers, Netherlands, 2001) pp. 145-165.

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Figures (4)

Fig. 1.
Fig. 1.

Current-voltage and light-current characteristics of the THz-QC laser. The inset shows the spectrum of laser driven at current density of 0.4 and 0.5 kA/cm2.

Fig. 2.
Fig. 2.

Schematics of the imaging set-up with THz-QC laser.

Fig. 3.
Fig. 3.

Spatial resolution of the imaging setup of Fig. 2. The inset shows the THz signal modulation during scanning across the line test pattern with 1 and 0.75 mm wide stripes.

Fig. 4.
Fig. 4.

White-light (a,b) and THz (c,d) images of rat brain frontal sections. The samples are about 30 μm thick and fixed onto a gold-coated flat mirror. The pixel size is 200 μm x 200 μm.

Equations (1)

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