Extremely-low-threshold and high-temperature operation in a photopumped ZnSe/ZnSSe blue laser

Abstract

A ZnSe/ZnSSe blue semiconductor laser was demonstrated to show very low threshold by direct photopumping of the ZnSe active layer. The lowest threshold at the excitation wavelength of 445 nm was 10 kW/cm2 at 300 K which is equivalent to the current density of 3.6 kA/cm2. This is the lowest threshold ever reported in II-VI photopumped lasers and is approaching the theoretically calculated threshold. The characteristic temperature of the threshold, which characterizes the temperature dependence of the threshold in the exponential form, was 124 K up to the measured 400 K and was comparable to III-V double-heterostructure lasers. The differential quantum efficiency remained the similar level up to 400 K and its decrease observed at 400 K was within 23% of the efficiency at 300 K.

An amido lithium tetra-zinc oxo complex: Synthesis and X-ray crystal structure of (μ4-oxo)-pentakis(μ2-diethylamido)-bis(N(ethyl)CHCH2)-lithium-tetrazinc

“…Despite some reports detailing its preparation by direct combination of diethyl zinc and diethylamine [13]. We, and others, have found that this led exclusively to the formation of [{di(ethyl)amido}ethylzinc] [3,8].…”

“…Several subsequent publications detail the syntheses of ½ZnRðNR 0 2 Þ [ [6][7][8][9] with special emphasis being paid to the bulky bis(trimethylsilyl)amide [10,11]. Less attention has been paid to more basic and less sterically hindered amines such as the di(alkyl)amines, although the syntheses of the [alkyl{di(alkyl)amido}zinc] complexes are well documented [9,[12][13][14]. A recent report highlights the utility of [aryl{di(alkyl)amido}zinc] complexes, generated in situ, for the preparation of a-functionalised organozincs [15].…”

Above room temperature near ultraviolet lasing from an optically pumped GaN film grown on sapphire

“…This value of T 0 is about two times larger than that of II-VI lasers ͑T 0 ϭϳ120 K for II-VI lasers͒, indicating that the lasing threshold is less sensitive to changes in temperature. 17,18 It is well known that high-temperature sensitivity of the lasing threshold usually limits the performance of a laser under high-temperature operation. 16 On the other hand, a weak temperature dependence for the lasing threshold implies that the high-temperature performance limit for laser operation can be significantly expanded.…”

Quest for Compact Blue Lasers for Optical Memories

“…In optically pumped blue lasers, the combination of improvement in the material quality, band edge emission and heterostructures has resulted in a room temperature laser [52][53][54][55][56]. The best result to date has been reported by Nakanishi et al in a structure of ZnSe/ZnSSe [56].…”