Optical sensing by using photonic quantum ring lasers and resonance-enhanced photodetectors

Abstract

We describe an optical sensor using photonic quantum ring lasers and resonance-enhanced photodetectors for the purpose of counting object discrimination. Due to the angle-dependent peak wavelength shift characteristics of the photonic quantum ring laser, an emission at an angle of 0ϳ30 deg from a perpendicular direction was reflected and absorbed in the resonance-enhanced photodetector, with a peak responsivity of 0.107 A/W at 757 nm. The use of the photonic quantum ring laser at an optimized angle in this monolithically integrated system, based on a distributed Bragg partial reflector structure, can lead to a compact, low cost, dust-free optical sensor and counter.

Electron emission from a semiconductor quantum ring under normally incident radiation

“…In figure 3(a) the threshold energy for which the electron starts emitting becomes a function of cross-sectional radius (r ), while it is independent of the circumference (C) of the ring. This is due to the fact that the velocity of electron emission depends only on the radial quantum numbers, and not on the quantum numbers arising from circumferential motion (see equation (7)). The variation of threshold energy with r will be shown in detail in a separate graph later.…”

“…The particular classes of nanostructures with the ring geometry are being intensively investigated due to the possibility a b 2r of experimental observations of the Aharonov-Bohm effect in these structures. Ring-shaped quantum dots with nanometre-scale radii have triggered much interest in theoretical and experimental investigations of their electric and optical properties [6][7][8][9][10]. In many respects, quantum rings are quantum dots with a particular confining potential.…”

Recent advances in enhancing the photodetector performance of 2D materials by combining them with organic thin films

“…As society enters the high-tech era, there is a growing demand for multifunctional photodetectors, such as in life sciences (X-rays, 90 MRIs, 91 CT scans, 92 and PET scans 93 ), communications and information technology (fiber-optic communications, 94 LIDAR, 95 photonics computing, 96 and optical sensing 97 ), security and military applications (night-vision, 98 infrared detection, 99 laser ranging, 100 and target identification 101 ), industry and manufacturing 102 (measuring, detecting and monitoring various physical parameters), etc. , which necessitates the development of new photodetectors, especially 2D/organic heterojunction detectors.…”

“…Traditional photodetectors can no longer meet the demand, especially in medicine, quantum communication, and satellite radar, and other more stringent requirements. 90–97,99–102 The rise of 2D materials has brought new opportunities for the fabrication of photodetectors, especially since 2004 when Novoselov et al obtained single-layer graphene by mechanical exfoliation. 112 2D materials, including graphene and its derivatives ( e.g.…”

Effect of electric field on the oscillator strength and cross-section for intersubband transition in a semiconductor quantum ring

“…The study of semiconductor nanostructures including quantum dots has attracted the attention of researchers over the last few years, mainly due to the rapid advancement and growth of nano-fabrication technology [1][2][3]. The motion of electrons becomes restricted along the reduced dimensions (∼ nm), which results in the quantization of energy states [1,4,5]. The restricted motion of the carriers leads to significant changes in both microscopic and macroscopic properties of the structure.…”