GaAs1−xBix/GaNyAs1−y type-II quantum wells: novel strain-balanced heterostructures for GaAs-based near- and mid-infrared photonics

Abstract

The potential to extend the emission wavelength of photonic devices further into the near- and mid-infrared via pseudomorphic growth on conventional GaAs substrates is appealing for a number of communications and sensing applications. We present a new class of GaAs-based quantum well (QW) heterostructure that exploits the unusual impact of Bi and N on the GaAs band structure to produce type-II QWs having long emission wavelengths with little or no net strain relative to GaAs, while also providing control over important laser loss processes. We theoretically and experimentally demonstrate the potential of GaAs1−xBix/GaNyAs1−y type-II QWs on GaAs and show that this approach offers optical emission and absorption at wavelengths up to ~3 µm utilising strain-balanced structures, a first for GaAs-based QWs. Experimental measurements on a prototype GaAs0.967Bi0.033/GaN0.062As0.938 structure, grown via metal-organic vapour phase epitaxy, indicate good structural quality and exhibit both photoluminescence and absorption at room temperature. The measured photoluminescence peak wavelength of 1.72 μm is in good agreement with theoretical calculations and is one of the longest emission wavelengths achieved on GaAs to date using a pseudomorphically grown heterostructure. These results demonstrate the significant potential of this new class of III-V heterostructure for long-wavelength applications.

Continuous-Wave Magneto-Optical Determination of the Carrier Lifetime in Coherent Ge1−xSnx/Ge Heterostructures

“…The thickness of the Ge 0.92 Sn 0.08 epilayer is systematically varied across the critical thickness (i.e., between 40 and 80 nm). This investigated range is in good agreement with results on III-V materials [50] and the values reported at a comparable Sn content in Ref. [22].…”

Impact of Disorder on the Optoelectronic Properties of GaNyAs1−x−yBix Al

“…28,69 We expect that a simliar k•pbased approach to that developed for (In)GaN y As 1−y and (In)GaAs 1−x Bi x can be reliably applied to compute, analyse and optimise the properties of devices based on type-I GaN y As 1−x−y Bi x heterostructures, but that detailed comparison to future experimental measurements will be required to ascertain the validity of such approaches when applied to type-II heterostructures based on N-and Bi-containing alloys. 70…”

Assessing the Nature of the Distribution of Localised States in Bulk GaAsBi

“…The incorporation of dilute quatities of bismuth into GaAs has been highlighted as a promising material system for a range of optoelectronic device applications, including telecommunications band (1550–1300 nm) lasers 1–3 , mid-IR photosensitive detectors 4–7 and multi-junction photovoltaics (PV) 8–10 . The application of dilute bismide alloys to multi-junction PV could offer a suitable pathway to realising a highly desirable 1.0 eV band-gap sub-cell, which is crucial for the development of future four junction solar cells.…”