Université de Neuchâtel

CO2 isotope sensor using a broadband infrared source, a spectrally narrow 4.4 μm quantum cascade detector, and a Fourier spectrometer

Hofstetter, Daniel ; Di Francesco, Joab F. ; Hvozdara, Lubos ; Herzig, Hans-Peter ; Beck, Mattias

In: Applied Physics B: Lasers and Optics, 2010, vol. 103, no. 4, p. 967-970

We report a prototype CO2 gas sensor based on a simple blackbody infrared source and a spectrally narrow quantum cascade detector (QCD). The detector absorption spectrum is centered at 2260 cm−1 (4.4 μm) and has a full width at half maximum of 200 cm−1 (25 meV). It covers strong absorption bands of two spectrally overlapping CO2 isotopomers, namely...

Université de Neuchâtel

23 GHz operation of a room temperature photovoltaic quantum cascade detector at 5.35 µm

Hofstetter, Daniel ; Graf, Marcel ; Aellen, Thierry ; Faist, Jérôme ; Hvozdara, Lubos ; Blaser, Stéphane

In: Applied Physic Letters, 2006, vol. 89, no. 061119, p. 1-3

We present a room temperature operated 5.35 µm quantum cascade detector which was tested at high frequencies using an optical heterodyne experiment. Two slightly detuned continuous wave distributed feedback single mode quantum cascade lasers were used to generate a beating signal. The maximum frequency at which the resulting microwave signal could be detected was 23 GHz. The cutoff...

Université de Neuchâtel

Room temperature, continuous wave operation of distributed feedback quantum cascade lasers with widely spaced operation frequencies

Wittmann, Andreas ; Giovannini, Marcella ; Faist, Jérôme ; Hvozdara, Lubos ; Blaser, Stéphane ; Hofstetter, Daniel ; Gini Emilio

In: Applied Physics Letters, 2006, vol. 89, no. 141116, p. 1-3

Lasing properties of room temperature, continuous wave operated distributed feedback (DFB) quantum cascade lasers are reported. A bound-to-continuum active region was used to generate a broad gain spectrum. As a result, first-order DFB lasers employing different periods allowed us to achieve single mode continuous wave emission at several wavelengths ranging from 7.7 to 8.3 µm at a...