Title :
Low-threshold lasing and Purcell effect in microdisk lasers at room temperature
Author :
Baba, Toshihiko ; Sano, Daisuke
Author_Institution :
Dept. of Electr. & Comput. Eng., Yokohama Nat. Univ., Japan
Abstract :
In this paper, we discuss the Purcell effect, which enhances the spontaneous emission rate, in microdisk lasers operating at room temperature by continuous wave photopumping. We theoretically analyzed the Purcell effect at room temperature by using the four-level rate equations that include the intraband relaxation and the nonradiative effect. We also fabricated 1.55-μm GaInAsP microdisk lasers with a minimum diameter of 1.7 μm and a minimum threshold power of 19 μW. Then, we measured the carrier lifetime in a 2.6-μm-diameter device by the phase-resolved spectroscopy method, and confirmed that the carrier lifetime was shortened to 1/10 of that in the as-grown epitaxial wafer at a low pump level. From the comparison between the theory and the experiment, we estimated the Purcell factor to be 6.7, the spontaneous emission factor to be 0.11, and the nonradiative lifetime to be 4 ns. The nonradiative lifetime was consistent with that estimated by another methods. We believe that this is the first demonstration of the Purcell effect in semiconductor microcavities at room temperature.
Keywords :
III-V semiconductors; arsenic compounds; carrier lifetime; gallium compounds; indium compounds; microcavity lasers; optical fabrication; optical pumping; semiconductor device models; semiconductor lasers; surface recombination; time resolved spectra; 1.55 mum; 1.7 mum; 19 muW; 2.6 mum; 20 degC; 4 ns; GaInAsP microdisk lasers; GaInAsP-InP; Purcell effect; carrier lifetime; continuous wave photopumping; four-level rate equations; low-threshold lasing; nonradiative lifetime; optical fabrication; phase-resolved spectroscopy; room temperature; semiconductor microcavities; spontaneous emission rate; Charge carrier lifetime; Equations; Laser theory; Life estimation; Lifetime estimation; Phase measurement; Power lasers; Spectroscopy; Spontaneous emission; Temperature;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/JSTQE.2003.819464