Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser

Hancock, G.; van Helden, J. H.; Peverall, R.; Ritchie, G. A. D.; Walker, R. J.
May 2009
Applied Physics Letters;5/18/2009, Vol. 94 Issue 20, p201110
Academic Journal
A continuous wave external cavity quantum cascade laser (EC-QCL) operating between 1872 and 1958 cm-1 has been used to make rotationally resolved measurements in the fundamental band of nitric oxide at 140 mTorr, and the ν2 band of water at atmospheric pressure. These measurements demonstrate the advantages of wide tunability and high resolution of the EC-QCL system. From direct absorption spectroscopy on nitric oxide a laser bandwidth of 20 MHz has been deduced and a sensitivity of 8.4×10-4 cm-1 Hz-1/2 was achieved. Wavelength modulation spectroscopy using current modulation enhances the sensitivity by a factor of 23 to 3.7×10-5 cm-1 Hz-1/2.


Related Articles

  • Room temperature type-II interband cascade laser. Yang, Rui Q.; Bradshaw, J. L.; Bruno, J. D.; Pham, J. T.; Wortman, D. E.; Tober, R. L. // Applied Physics Letters;7/15/2002, Vol. 81 Issue 3, p397 

    A mid-IR (3.3-3.5 µm) type-II interband cascade laser has been demonstrated at temperatures up to 300 K in pulsed mode and 150 K in cw mode. Threshold current densities as low as 13.2 A/cm² and power efficiencies as large as 17% have been achieved under cw conditions at 80 K.

  • High-power λapprox. 8 μm quantum cascade lasers with near optimum performance. Gmachl, Claire; Tredicucci, Alessandro; Capasso, Federico; Hutchinson, Albert L.; Sivco, Deborah L.; Baillargeon, James N.; Cho, Alfred Y. // Applied Physics Letters;6/15/1998, Vol. 72 Issue 24 

    Quantum cascade (QC) lasers emitting at λapprox. 8 μm with a power performance equal to short-wavelength (λapprox. 5 μm) QC lasers are reported. The device improvement is mainly achieved by a design of the injector/relaxation region, which at laser threshold allows resonant carrier...

  • A quasi-one-dimensional model for cascade gasdynamic lasers. Bahrampour, A.R.; Farrahi, R.-M. // Applied Physics B: Lasers & Optics;Jul2003, Vol. 76 Issue 7, p749 

    .A quasi-one-dimensional model for cascade 16-μm gasdynamic lasers is developed. Based on this model, the effect of cavity parameters on the output pulse is studied. Also, a comparison with externally pumped lasers is made. It is shown that this type of 16-μm gasdynamic lasers can...

  • Cascade four-wave mixing in semiconductor lasers. Nietzke, R.; Fenz, P.; Elsässer, W.; Göbel, E. O. // Applied Physics Letters;10/26/1987, Vol. 51 Issue 17, p1298 

    Highly efficient cascade frequency mixing signals are generated in a nearly degenerate intracavity four-wave mixing experiment in a GaAs/(GaAl)As semiconductor laser. This method allows a consistent quantitative determination of the third-order nonlinear optical susceptibility within the gain...

  • Short wavelength intersubband emission from InAs/AlSb quantum cascade structures. Barate, D.; Teissier, R.; Wang, Y.; Baranov, A. N. // Applied Physics Letters;8/1/2005, Vol. 87 Issue 5, p051103 

    The InAs/AlSb material system is a promising candidate for the development of short wavelength quantum cascade lasers because of the large conduction band offset of 2.1 eV. In this letter, we present a study of room temperature electroluminescence of InAs/AlSb quantum cascade structures as a...

  • A carbon monoxide and thermometry sensor based on mid-IR quantum-cascade laser wavelength-modulation absorption spectroscopy. Vanderover, J.; Wang, W.; Oehlschlaeger, M. // Applied Physics B: Lasers & Optics;Jun2011, Vol. 103 Issue 4, p959 

    mid-infrared wavelength modulation spectroscopy (WMS) absorption sensor utilizing a quantum cascade laser (QCL) source for carbon monoxide detection at 4.6 μm and high-temperature thermometry has been developed and demonstrated. Measurements are made in a room-temperature gas cell and in...

  • Positron and gamma-photon production and nuclear reactions in cascade processes initiated by a.... Shkolnikov, P.L.; Kaplan, A.E. // Applied Physics Letters;12/15/1997, Vol. 71 Issue 24, p3471 

    Examines the role of sub-terawatt femtosecond lasers in producing positron and gamma-photon and nuclear reactions in cascade processes. Implication of produced nuclear radiation for material science, medicine and nuclear engineering researches; Generation of laser-plasma electrons interacting...

  • Organocatalytic asymmetric synthesis of chiral nitrogenous heterocycles and natural products. Yu, Jie; Zhou, Ya; Chen, Dian-Feng; Gong, Liu-Zhu // Pure & Applied Chemistry;Jul2014, Vol. 86 Issue 7, p1217 

    Nitrogen-containing chiral heterocycles represent important structural elements with wide occurrence in natural and unnatural compounds exhibiting important biological activities. Herein, we describe our recent endeavors directed toward the Brønsted acid-catalyzed 1,3-dipolar cycloaddition...

  • The impact of the operating field strength on the lasing properties of GaAs/(Al,Ga)As quantum-cascade lasers. Schrottke, L.; Giehler, M.; Hey, R.; Grahn, H. T. // Journal of Applied Physics;9/1/2006, Vol. 100 Issue 5, p053102 

    The gain coefficient of several GaAs/AlxGa1-xAs quantum-cascade lasers (QCLs) with a nominal Al content of x=0.45 has been calculated as a function of transition energy and electric field strength. We solve the Schrödinger and Poisson equations self-consistently in the framework of a linear...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics