Frequency-agile terahertz-wave spectrometer for high-resolution gas sensing

A tabletop, frequency-agile terahertz-wave spectrometer was developed based on an injection-seeded terahertz-wave parametric generator. High-resolution (<100MHz) spectra of polar gases can be measured in a wide frequency region (0.6–2.4THz) within a short time (several minutes) with this spectrometer. To demonstrate the potential of this system, the authors performed real-time detection of the absorption line due to rotational transitions of the water molecule and determined their pressure-broadening coefficient.

[1]  Kodo Kawase,et al.  Achromatically injection-seeded terahertz-wave parametric generator. , 2002 .

[2]  Kodo Kawase,et al.  Injection-seeded terahertz-wave parametric generator with wide tunability , 2002 .

[3]  Richard H. Pantell,et al.  Continuously tunable submillimeter wave source , 1975 .

[4]  R. Davies,et al.  Theoretical calculations of N2-broadened halfwidths of H2O using quantum Fourier transform theory. , 1983, Applied optics.

[5]  Jun-ichi Nishizawa,et al.  THz imaging of nucleobases and cancerous tissue using a GaP THz-wave generator , 2005 .

[6]  E. Linfield,et al.  Terahertz semiconductor-heterostructure laser , 2002, Nature.

[7]  K. Evenson,et al.  Tunable far-infrared laser spectroscopy , 1988, Annual Meeting Optical Society of America.

[8]  Jun-ichi Nishizawa,et al.  Tunable terahertz wave generation in the 3- to 7-THz region from GaP , 2003 .

[9]  J. Nishizawa,et al.  Low-threshold semiconductor Raman laser , 1983 .

[10]  A.C.P. Alves,et al.  Frontiers of Laser Spectroscopy of Gases , 1988 .

[11]  Hiromasa Ito,et al.  All-solid-state, narrow linewidth, wavelength-agile terahertz-wave generator , 2006 .

[12]  J. W. C. Johns,et al.  High-resolution far-infrared (20–350-cm −1 ) spectra of several isotopic species of H 2 O , 1985 .

[13]  D. Grischkowsky,et al.  Far-infrared terahertz time-domain spectroscopy of flames. , 1995, Optics letters.

[14]  Samuel D. Gasster,et al.  Foreign-gas collision broadening of the far-infrared spectrum of water vapor , 1988 .