Difference-frequency pulse generation in quantum well heterolasers

Terahertz generation via intracavity mixing in mode-locked dual-wavelength lasers

“…It is worth noticing, that under strong pumping the ratio between equilibrium population differences q is of the order of unity. 3 In case of q = 1 and ζ = 1, η = 0 it is possible to obtain exact expression for nonlinear polarization:…”

“…3 A layer with the dielecrtic function 2 surrounded by layers with 1 < 2 (see Fig. 1) provides waveguiding of optical and IR or THz radiation.…”

“…The mode-locking regime of optical generation for one or both lasing fields allows one to enhance significantly the output power of difference-frequency signal in comparison with continuous-wave operation due to further increase of intensities of mixing fields. 3 In the present paper we consider a simple model of mode-locked dual-wavelength nonlinear-mixing laser, which makes it possible to derive an explicit formula for the intensity and shape of the generated pulses and to show that this method is capable of producing picosecond pulses at about 1 GHz repetition rate with the peak power of the order of 0.1 mW and 0.01 mW at 0.05 mm and 0.1 mm wavelengths, respectively. Even average output power can be greatly increased (from several to few tens times) if one implements the mode-locking regime for both optical fields of the dual-wavelength heterolaser.…”

Terahertz generation by means of optical lasers

“…Recently a new type of dual pumping was proposed for efficient intracavity DFG. The semiconductor material with high non-resonant bulk nonlinearity, or the nonlinearity due to the resonant intersubband transitions in quantum wells, is placed inside a mode-locked dual-wavelength heterolaser [131,132]. These monolithically integrated devices combine the advantages of electrically pumped semiconductor lasers and nonlinear optical sources.…”