Emission and detection of terahertz radiation using two-dimensional plasmons in semiconductor nanoheterostructures for nondestructive evaluations

Abstract

Abstract. The recent advances in emission and detection of terahertz radiation using two-dimensional (2-D) plasmons in semiconductor nanoheterostructures for nondestructive evaluations are reviewed. The 2-D plasmon resonance is introduced as the operation principle for broadband emission and detection of terahertz radiation. The device structure is based on a high-electron-mobility transistor and incorporates the authors' original asymmetrically interdigitated dual-grating gates. IntroductionIn the research of modern terahertz (THz) electronics, development of compact, tunable, and coherent sources operating at THz frequencies is one of the hottest issues.1 Two-dimensional (2-D) plasmons in submicron transistors have attracted much attention due to their nature of promoting emission and detection of electromagnetic radiation in the THz range. The channel of a transistor can act as a resonator for plasma waves, the charge-density waves of collectively excited 2-D electrons. The plasma frequency depends on the resonator dimensions and the density of 2-D electrons. It can reach the sub-THz or even THz range for gate lengths of a micron and submicron (nanometer) size. Therefore, different devices/structures of micron and submicron sizes supporting low-dimensional plasmons were intensively studied as possible candidates for solid-state far-infrared (FIR)/THz sources 2-18 and detectors. [19][20][21][22][23][24][25][26][27][28][29][30] Mechanisms of plasma wave excitation/emission can be divided (by convention) into two types: (1) incoherent and (2) coherent. The first is related to thermal excitation of broadband nonresonant plasmons by hot electrons.2-7 The second is related to the plasma wave instability mechanisms like Dyakonov-Shur (DS) Doppler-shift model 8 and/or Ryzhii-Satou-Shur (RSS) transit-time model, 17,18 where coherent plasmons can be excited either by hot electrons or by optical phonon emission under near ballistic electron motion. 31 On the other hand, hydrodynamic nonlinearities of 2-D plasmons in highelectron-mobility transistors (HEMTs) are promising for fast and sensitive rectification/detection of THz radiation.

A high electron mobility phonotransistor

“…2DEG structures have been heavily researched in the THz community with novel structures being designed as plasmon emitters (for a review see ref. 34 ). A potential route for future investigation is using acoustic waves to modify the carrier concentration in these structures providing the possibility for fast modulation of the signals in these devices.…”

Широкоапертурная Асферическая Оптика Для Формирования Субволновой Каустики Пучка Терагерцового Электромагнитного Излучения

“…Предложенная АЛ может быть использована в различных областях ТГц науки и техники. Перспективные приложения ТГц широкоапертурной оптики связаны с медицинской диагностикой злокачественных новообразований организма человека [20], в частности: (i) с неинвазивной диагностикой базальноклеточного рака и здоровой кожи [60][61][62][63] [27][28][29]73], контроля качества продуктов питания [74,75], а также продуктов химической и фармацевтической промышленности [21][22][23]. Аберрации АЛ были скорректированы для малого углового поля зрения, а соответственно они могут использоваться исключительно для задач ТГц спектроскопии и имиджинга, предполагающих поточечное сканирование поверхности образца сфокусированным пучком ТГц излучения.…”

“…Благодаря отмеченным свойствам ТГц излучение находит применение в различных областях науки и техники [1]. Показана возможность применения методов ТГц спектроскопии [9][10][11][12], имиджинга [13][14][15] и томографии [16,17] в биологии, медицине [18][19][20], материаловедении, химии и фармацевтике [21][22][23], в задачах обеспечения безопасности жизнедеятельности [24][25][26], неразрушающего технологического и эксплуатационного контроля конструкционных материалов [27][28][29].…”

Design of terahertz narrowband filter based on surface plasmon polaritons of metal–dielectric–metal structure with circular loop arrays

“…1 For its significant scientific and technological potentials, research of SP in a terahertz (THz) frequency region has been of great interest for decades. [3][4][5][6] According to their different resonance properties, SP could be divided as propagation surface plasmons (PSP) and localized surface plasmons (LSP). [3][4][5][6] According to their different resonance properties, SP could be divided as propagation surface plasmons (PSP) and localized surface plasmons (LSP).…”