Optical property of GaAsP/AlGaAs strained-layer quantum well grown on GaAs-(111)B substrate

Abstract

GaAs1−xPx/AlyGa1−yAs (x=0.07–0.15, y=0.3) strained-layer quantum wells have been grown on GaAs-(111)B substrates by low-pressure metalorganic vapor phase epitaxy and characterized by photoluminescence (PL) spectroscopy. Evident energy blue shifts of the excitonic transition peaks (some of them as large as 33 meV) were achieved by increasing the excitation power during the PL measurement. The large optical nonlinearity mainly due to the strain-induced piezoelectric field screened by the photoexcited carriers, is comparable to, or larger than, the reported values for a self-electro-optical effect device or other (111)-oriented strained-layer quantum well structures which are composed of InGaAs/GaAs or GaAs/GaAsP. This fact indicates that our (111)-GaAsP/AlGaAs strained-layer quantum well is a good candidate for making optoelectronic devices like optical switches and modulators.

First-principles calculations of band offsets

“…The GaAsP-GaAlAs strained-layer quantum well grown on a GaAs substrate is of technological significance, mainly because of its large optical nonlinearity. Zhang et al [1] have demonstrated that the excitonic transition peaks can achieve an energy blue-shift as large as 33 meV during photoluminescence measurements. Thus the GaAsP-GaAlAs strainedlayer quantum well is a good candidate for making optoelectronic devices such as optical switches and modulators.…”

Optical property of a novel (111)-oriented quantum structure

“…The MOVPE growth conditions for the ͑GaAsP͒-͑GaAs/AlGaAs MQWs͒-͑GaAsP͒-͑GaAs/AlGaAs MQWs͒-͑GaAsP͒ t-u-t-u-t quantum structure are similar to the ones for the ͑111͒-GaAsP/AlGaAs strainedlayer quantum well structures, which are described in detail in Ref. 11. Figure 2 demonstrates the schematic of GaAs 1Ϫx P x -GaAs/Al y Ga 1Ϫy As MQWs-GaAs 1Ϫx P x -GaAs/ Al y Ga 1Ϫy As MQWs-GaAs 1Ϫx P x ͑xϭ0.15, yϭ0.3͒ t-u-t-u-t quantum structure.…”

“…In other words, it is possible to make fully optically operated devices by using these ͑111͒-oriented strained-layer quantum well structures. In an earlier letter, 11 we reported a detailed photoluminescence ͑PL͒ study on the ͑111͒-GaAsP/AlGaAs strained-layer quantum well structures which has an obvious advantage over the most extensively studied ͑111͒-InGaAs/GaAs quantum well system, in that the strain or the strain-induced electric field in the quantum wells and the energy band offset at the heterointerface can be adjusted independently of each other by changing the phosphorus and aluminum composition, respectively.…”

“…11 This, however, should not hinder this novel quantum structure from practical application. In fact, if the number of the quantum wells incorporated in the unstrained regions or the barrier layer thickness is decreased, the built-in electric field distributed in the quantum wells as well as the energy blue shift could be significantly increased.…”

MAGNETIC FIELD, PRESSURE AND TEMPERATURE DEPENDENT OPTICAL PROPERTIES IN A GaAs 9.0 P 1.0 QUANTUM DOT

“…The electronic and optical properties can be significantly modified by the strain effects and in fact, these properties are improved with the inclusion of strain effects [3]. GaAsP quantum well structures have been grown by means of MOVPE and the strain-induced piezoelectric field has been studied and it is found that it can be adjusted by the energy band offset [4]. The optical properties of tensile-strained GaAsP/GaInP square quantum wells grown by MOCVD have been investigated with various characteristics of the PL spectra [5].…”