Magnetotransport in GaAs δ-doped by Sn

Beginning from the 1990s, an ever-lasting interest in the THz spectroscopy and THz instruments has produced wide progress in the development of high-speed THz detectors. The constantly growing requirements aimed at the increase of spectral resolution, sensitivity, and acquisition rate of THz detectors have attracted much attention in this field till nowadays. In the present review, we summarize the most recent advances in the THz photodetectors based on semiconductor structures with quantum confinement of an electron gas. Their main advantages over existing detectors are fast response time, increased spectral resolution, and multicolor operation thanks to the variability of their designs and band structure engineering. These all allow using them in various important applications as single photon detection, THz heterodyne detection, continuous monitoring of toxic gases, THz free space communications, and radio astronomy, as well.

Section: Quantum Wires-based Thz Detectorsmentioning

confidence: 99%

Recent advances in THz detectors based on semiconductor structures with quantum confinement: a review

Yachmenev¹,

Хабибуллин²,

Пономарев³

2022

“…The first theoretical and experimental studies of the ungated Sn-doped GaAs structures were reported in [26,27]. Those works demonstrated that the Sn-dopants are predominantly accumulated at the step edges of the atomic terraces of the vicinal GaAs substrate enabling the formation of a dense array of the one-dimensional (1D) Sn-nanothreads (Sn-NTs) channels.…”

Section: Introductionmentioning

confidence: 99%

Sub-terahertz FET detector with self-assembled Sn-nanothreads

Пономарев

Lavrukhin

Yachmenev

et al. 2019

We report on the design, evaluation and fabrication of the sub-terahertz (sub-THz) detector using a GaAs gated field-effect transistor with a buried quasi-two-dimensional electron gas created by the self-assembled Sn-nanothreads (Sn-NTs) embedded into the GaAs channel. This GaAs-Sn-NTs detector efficiently detects a sub-THz radiation at cryogenic and room temperatures (CT and RT, respectively). Two possible detection mechanisms are the bolometric mechanism due to electron heating by the sub-THz radiation and the mechanism related to the rectification of the decayed plasmonic oscillations. We developed a classical self-consistent device model of the bolometric detection involving the Poisson equation and the electron density of states and estimated responsivity and noise-equivalent power of the detector. The measured I-V characteristics and the photoresponse to the incident sub-THz radiation at CT and RT are in reasonable agreement with our model. The detector demonstrates a better performance than semiconductor-based hot-electron bolometers and quantum-well/dot IR and THz photodetectors.

“…The theoretical and experimental studies of the ungated Sn-doped GaAs structures were discussed previously in [27,28]. The authors demonstrated that Sn-dopants predominantly are accumulated at the step edges of the atomic terraces of the vicinal GaAs substrate that enables the formation of a dense array of the one-dimensional (1D) channels.…”

Section: Introductionmentioning

confidence: 99%

Lateral terahertz hot-electron bolometer based on an array of Sn nanothreads in GaAs

Пономарев

Lavrukhin

Yachmenev

et al. 2018

We report on the proposal and the theoretical and experimental studies of the terahertz hot-electron bolometer (THz HEB) based on a gated GaAs structure like the field-effect transistor with the array of parallel Sn nanothreads (Sn-NTs). The operation of the HEB is associated with an increase in the density of the delocalized electrons due to their heating by the incoming THz radiation. The quantum and the classical device models were developed, the quantum one was based on the self-consistent solution of the Poisson and Schrödinger equations, the classical model involved the Poisson equation and density of states omitting quantization. We calculated the electron energy distributions in the channels formed around the Sn-NTs for different gate voltages and found the fraction of the delocalized electrons propagating across the energy barriers between the NTs. Since the fraction of the delocalized electrons strongly depends on the average electron energy (effective temperature), the proposed THz HEB can exhibit an elevated responsivity compared with the HEBs based on more standard heterostructures. Due to a substantial anisotropy of the device structure, the THz HEB may demonstrate a noticeable polarization selectivity of the response to the in-plane polarized THz radiation. The features of the THz HEB might be useful in their practical applications in biology, medicine and material science.