Theoretical investigation of optical intersubband transitions and infrared photodetection in β-(AlxGa1 − x)2O3/Ga2O3 quantum well structures

Abstract

We provide theoretical consideration of intersubband transitions designed in the ultrawide bandgap Aluminum Gallium Oxide ((AlxGa1-x)2O3)/Gallium Oxide (Ga2O3) quantum well system. Conventional material systems have matured into successful intersubband device applications such as large area quantum well infrared photodetector (QWIP) focal plane arrays for reproducible imaging systems but are fundamentally limited via maximum conduction band offsets to mid-and long-wavelength infrared applications. Short-and near-infrared devices are technologically important to optical communications systems and biomedical imaging applications, but are difficult to realize in intersubband designs for this reason. In this work, we use a first-principles approach to estimate the expansive design space of monoclinic β-(AlxGa1x)2O3/Ga2O3 material system, which reaches from short-wavelength infrared (1-3 µm) to far infrared (>30 µm) transition wavelengths. We estimate the performance metrics of two QWIPs operating in the long-and short-wavelength regimes, including an estimation of high roomtemperature detectivity (~ 10 11 Jones) at the optical communication wavelength λp = 1.55 µm.Our findings demonstrate the potential of the rapidly maturing (AlxGa1-x)2O3/Ga2O3 material system to open the door for intersubband device applications.

Enhancing detectivity in mid-infrared photodetectors through structural parameter engineering in HgSe-HgTe colloidal quantum dots

“…The most important performance parameter that characterizes the sensitivity and the general performance of IR photodetectors is the detectivity. The detectivity is considered to be a main figure of merit of the detector and is defined as 44 D*=R[AdΔf]1/2/itn.…”

Steady-state and transient electronic transport properties of β-(Al x Ga1–x )2O3/Ga2O3 heterostructures: An ensemble Monte Carlo simulation

“…[6,7] In particular β -(Al x Ga 1−x ) 2 O 3 /Ga 2 O 3 heterostructures can be formed, [8] and the introduction of ternary alloys and the formation of heterostructures can significantly increase the number of possible applications and the performance of devices. [9] Knowledge about transport properties is a fundamental instrument for any physicist or engineer involved in technology design and preparation of semiconductor-based devices. Thus, the electron transport properties in β -(Al x Ga 1−x ) 2 O 3 /Ga 2 O 3 heterostructures must be understood in depth.…”