Temperature dependence of GaAs random laser characteristics

Abstract

We show the temperature-dependent random lasing characteristics of photoexcited GaAs powders from 30 to 300 K. The lasing properties strongly depend on the temperature, i.e., the lasing peak energy increases and the threshold excitation power decreases as the temperature decreases. A theoretical model, in which the gain spectra of heavily doped n-GaAs are taken into consideration, well describes the temperature dependence of the lasing peak energy. The temperature dependence of the threshold excitation power can be also explained by the model qualitatively.

Origins of lasing emission in a resonance-controlled ZnO random laser

“…In previous works [7,8], we have shown that the lasing peak position of a semiconductor (normal) random laser corresponds to the maximum of the gain spectrum calculated by using its physical parameters, not using its structural parameters. For ZnO, the optical gain spectrum g ( ) ω can be obtained from [22]:…”

“…In the defect-site lasing system, the gain is achieved by light emission from ZnO powder surrounding the defect site, and then, the localized light field is not restricted in the defect site itself but properly penetrates into the ZnO powder area. The single sharp emission peak is also 7 Because of the limitation of our pumping laser pulse power, the lasing measurments were performed at 300 K using the experimental setup described in [17]. observed at low temperatures (T = 20 and 180 K, figure 1(c)).…”

“…Random lasing from randomly shaped and sized semiconductor nanopowders (i.e., normal random lasing) occurs at the wavelength of its maximum optical gain [7], rather than at a specific resonance wavelength of the scatterer. Since the wavelength at the maximum optical gain of a semiconductor depends on the temperature, the lasing wavelength of the normal random laser gradually shifts in accordance with the temperature-dependent optical gain spectra.…”

Temperature-dependent internal photoemission probe for band parameters

“…Influence of the band tailing on E f is believed to be negligible. 39 Another possible influence on the IPE yield could be from the difference in effective masses between the emitter and barrier. This was previously discussed by Chen et al 40 They obtained a yield function containing effective masses based on interband transitions from VB to CB.…”

Discrete-mode ZnO microparticle random laser

“…This is because the lasing peaks usually appear around the gain spectrum peak of the amplification medium in random lasers [14,15]. To evaluate the gain properties of the present ZnO samples, the light emission spectra of the particle films excited just below I th are shown in Fig.…”