InGaAs-Based Well–Island Composite Quantum-Confined Structure with Superwide and Uniform Gain Distribution for Great Enhancement of Semiconductor Laser Performance

Abstract

In the development of semiconductor lasers, it has been a dream all along to simultaneously obtain extremely wide and uniform gain distribution, because such a gain configuration can greatly enhance semiconductor laser performance. Hence, it has also been a huge challenge to realize this dream so far. In this paper, we are reporting a special InGaAs-based well–island composite quantum-confined structure, with which the best results to date in achieving both superwide and very uniform gain and power distributions are obtained. The spectral flatness of the output power can reach 0.1 dB, and the gain bandwidth is broadened to 6-fold broader than the fwhm (full width at half-maximum) of the standard gain spectrum from a classic InGaAs quantum well under the same carrier density. The formation of the well–island composite quantum-confined structure is associated with the indium-rich island effect in the material growth. The great significance of this work lies in that it is making the above dream come true, since it not only can tremendously increase the spectral tuning range of an InGaAs-based semiconductor laser but also exhibits a great potential on achieving uniform output power over the full spectral tuning range of the laser.

Quantum Confined Indium-Rich Cluster Lasers with Polarized Dual-Wavelength Output

“…The injection energy is 112.4 mJ. Three peaks are observed in the measured PL spectrum, in which two extra peaks appear due to the emissions from the In 0.15 Ga 0.85 As and In 0.12 Ga 0.88 As regions . With the Gaussian simulation, it is found that the combination of three Gaussian spectra with peaks at 980, 970, and 930 nm is exactly identical to the experimental PL spectrum.…”

Light Emitting Devices Based on Quantum Well-Dots

“…In [31], significant depolarization of the heavy-hole-related electroluminescence was observed and attributed to in-plane strain fields caused by modulations of In composition. In reference [27], a special InGaAs-based well-island composite quantum-confined structure was demonstrated, and both super-wide and very uniform gain and power distributions were obtained. The spectral flatness of the output power reached 0.1 dB, and the gain bandwidth was broadened to six-folds broader than FWHM (full width at half the maximum) of the standard gain spectrum from a classic InGaAs quantum well under the same carrier density.…”

“…A number of research groups have investigated nanostructures that can be considered as intermediate cases between QWs and QDs. These structures were referred to as modulated quantum wells [16,17], as quantum wires [18][19][20][21][22][23][24], as 'Wires-on-Well' (WoW) [25,26], and as 'Well-Island' [27]. One approach is to use a dense array of small-sized QDs [21,28,29].…”

“…Despite the rather interesting results obtained for photovoltaic converters based on various nanostructures of mixed dimensionality, including WoW, QWR, QWDs, etc. [25,26], the reports on light-emitting devices were scarce [27,31]. In this review article, we mostly focus on the application of QWDs to light emitting devices, describe their basic properties, and demonstrate fundamental advantages.…”

Экспериментальное и теоретическое исследование спектров фоточувствительности структур с квантовыми ямами-точками In-=SUB=-0.4-=/SUB=-Ga-=SUB=-0.6-=/SUB=-As оптического диапазона 900-1050 nm

“…В последнее время большой интерес вызывают наноструктуры, обладающие свойствами, промежуточными между свойствами КЯ и КТ [11][12][13][14][15]. Они вносят сравнимый с КЯ вклад в фототок, и при их формировании, как и в случае КТ, происходит бездефектная релаксация упругих напряжений.…”