Characteristics of an XeF (C–A) laser emitting visible light as a result of optical pumping by surface-discharge radiation

Abstract

We study theoretically the effects of exciton bound states on the reflectivity of semiconductor superlattices and thin films. We consider direct gap semiconductors and assume extrinsic potentials near surfaces to model the exciton interactions. Using a multistep method and the 4 × 4 transfer matrix approach, we solve analytically the polariton exciton equations for s-polarized light. Results are presented for the A n=1 excitonic transition of CdS and interpreted in terms of exciton bound states and Fabry-Pérot resonances of the transverse modes. We find that for the superlattice the reflectivity peaks of the high-energy bound states are notably enhanced as compared with the corresponding ones of the single isolated film.

State and prospects of the XeF(C-A) optically pumped laser

“…It was shown in [9] that G 18 1 for the lasers in the visible spectral region with L O.5.2m The gain for CA transition typically achieved in experiments is low (-O.3% cm') since the cross section for stimulated emission is low (40'7cm2) and the linewidth is large 7O nm [2]. Substituting g = 3103cm'.…”

“…The speed of the bleaching wave expansion is much higher than that of the discharge. For typical experimental conditions it equals to about 10 km/s compared to the discharge speed of about 1 km/s [2][3][4]7]. Thus, it is possible to consider the pumping discharge as an infinitely thin linear light source.…”

State of and prospects for XeF(C−A) optically pumped lasers

“…It has been shown [12] that G ~ 18 + 1 for lasers with Lc '~ 0.5 -2 m in the visible spectral region. The gain of the C-A transition obtained in experiments is low (~ 0.003 cm -1) due to the small gain cross-section (.,.10 -1~ cm 2) and broad gMn spectral width (~70 nm) [5]. By substituting g = 3.10 -a cm -t, G = 18, and Lc/L,= 2 into Eq.…”

“…The speed of the bleaching wave expansion is much higher than that of the discharge. For typical experimental conditions, it equals ,,~10 km/s, whereas the discharge speed is approximately 1 km/s [3][4][5][6][7].…”

“…Extensive experimental investigations of the exploded wire technique have resulted in energies up to 15 J with an efficiency of 4.10 -4 [3,4]. The next step was taken in [5][6][7], where the laser was pumped by an open surface discharge capable of operating in a pulse repetitive mode. Energies of up to 117 J were obtained with an efficiency of ,-~ 1.3-10 -3.…”