Latest developments in GaN-based quantum devices for infrared optoelectronics

Abstract

In this work, we summarize the latest progress in intersubband devices based on GaN/AlN nanostructures for operation in the near-infrared. We first discuss the growth and characterization of ultra-thin GaN/AlN quantum well and quantum dot superlattices by plasma-assisted molecular-beam epitaxy. Then, we present the performance of nitride-based infrared photodetectors and electro-optical modulators operating at 1.55 lm. Finally, we discuss the progress towards intersubband light emitters, including the first experimental observation of intersubband photoluminescence in nitride nanostructures.

Controlled Synthesis of AlN/GaN Multiple Quantum Well Nanowire Structures and Their Optical Properties

“…AlN/GaN superlattices have been extensively used in planar-structured quantum electronic and photonic devices, ranging from high mobility transistors, quantum cascade lasers, infrared photodetectors, , to distributed Bragg reflectors. , While the AlN/GaN nanowire superlattices have been demonstrated using molecular beam epitaxy technique, the growth of these III-nitride heterojunction nanostructures by metal–organic chemical vapor deposition (MOCVD) has met little success. In this work, we demonstrated the growth of unique GaN/(AlN/GaN) m ( m = 3, 13) MQW nanowire heterostructures using MOCVD and correlate the observed blue-shifted luminescence in photoluminescence to the size-associated confinement effect in quantum well structure by combining cross-sectional cathodoluminescence (CL) analysis and theoretical study of electron energy states in MQWs.…”

“…AlN/GaN superlattices have been extensively used in planarstructured quantum electronic and photonic devices, ranging from high mobility transistors, 25 quantum cascade lasers, 26 infrared photodetectors, 27,28 to distributed Bragg reflectors. 29,30 While the AlN/GaN nanowire superlattices have been demonstrated using molecular beam epitaxy technique, 14 the growth of these III-nitride heterojunction nanostructures by metal−organic chemical vapor deposition (MOCVD) has met little success.…”

Spectral Sensitivity Tuning of Vertical InN Nanopyramid-Based Photodetectors

“…Aside from Si-, Ge-, and GaInAsbased photodetectors [1][2][3] -which have bridged this gap by now -photodetectors also based on the III-nitride material system have gained considerable importance. [4][5][6] Since the fundamental InN band gap energy has been revised from 1.8-2.1 to 0.65-0.7 eV, [7][8][9] III-nitride photodetectors benefit from their inherent spectral selectivity, which permits the detection edge to be tailored from the UV (AlN) to the IR (InN) continuously by composition adjustment of ternary Ga x In 1Àx N and Al y In 1Ày N alloys. In addition, unique material properties such as chemical inertness, low susceptibility to radiation damage, 10,11) as well as satisfying thermal conductivity 12,13) make III-nitrides highly suitable for highpower and high-frequency optoelectronics operating under harsh environmental conditions.…”

III-Nitride-Based Quantum Dots and Their Optoelectronic Applications

“…Some efforts have been shifted to the next generation III-nitride-based quantum dot (QD) devices such as QD lasers [12], QD LEDs [13], QD infrared photodetectors [14], and QD solar cells (SCs) [15]. Three dimensional quantum confinement of quantum dots gives rise to complete localization of electrons and holes and a discrete energy spectrum with δ-function-like density of states, which increase the overlap of electron and hole wave functions and improve the recombination rate of carriers.…”