A. A. Lastovkin, A. V. Ikonnikov, A. V. Antonov, V. Ya. Aleshkin, V. I. Gavrilenko, Yu. G. Sadof'ev, “Variation of the emission frequency of a terahertz quantum cascade laser”, Pisma v Zhurnal Tekhnicheskoi Fiziki, 2016, Volume 42, Issue 5,Pages <nobr>15

Variation of the emission frequency of a terahertz quantum cascade laser

A. A. Lastovkin^ab, A. V. Ikonnikov^ab, A. V. Antonov^ab, V. Ya. Aleshkin^ab, V. I. Gavrilenko^ab, Yu. G. Sadof'ev^c

^a Institute for Physics of Microstructures, Russian Academy of Sciences, Nizhnii Novgorod
^b National Research Lobachevsky State University of Nizhny Novgorod
^c P. N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow

Abstract: The variation of the emission frequency of a quantum cascade laser of the 3.2 THz range within a single radiation pulse was studied using high-resolution Fourier spectroscopy. A significant (108 MHz) increase in frequency in the first 4 $\mu$s of a pulse was found. This increase is attributed to a change in the electron part of permittivity of the laser active region coinciding with a rise in the emission intensity. The frequency dropped by 81 MHz in the following 40 $\mu$s of a radiation pulse due to a change in the lattice part of permittivity occurring as the laser active region was heated during a radiation pulse.

Received: 24.09.2015