Interaction of gated and ungated plasmons in two-dimensional electron systems

Abstract

Unique properties of plasmons in two-dimensional electron systems (2DESs) have been studied for many years. Existing theoretical approaches allow for analytical study of the properties of ungated and gated plasmons in two fundamental, ideal cases -the 2DES in dielectric environment and under an infinite metallic gate, respectively. However, it is for the first time that we introduce an analytical theory of the interaction of gated and ungated plasmons in partly gated 2DES. Generally, a finitewidth gate is formed by a metallic strip placed over an infinite plane hosting 2D electrons. Our solution, in particular, describes the propagating plasmon modes with their charge density having N nodes under the gate. In this regard, a new mode with N = 0 has been found in addition to the gapped modes with N = 1, 2, ... previously derived from numerical calculations. Unexpectedly, this fundamental plasmon mode has been found to differ substantially from the rest. In fact, it is characterised by gapless square root dispersion and represents a hybrid of gated and ungated plasmons. In contrast to the higher modes, the currents and lateral fields of the fundamental mode are localized mainly to the outside area in the vicinity of the gate. Heretofore, such a 'near-gate plasmon' has never been considered.

Non-local terahertz photoconductivity in the topological phase of Hg1−xCdxTe

“…One more possibility could be related to the terahertz excitation of magnetoplasmons. They also change their chirality upon the magnetic field reversal 28 , 29 . However, flipping the photocurrent polarity upon bias switching may not be explained by this hypothesis.…”

Rectification of AC Electric Current at the Edge of 2D Electron Gas

“…The field consists of the field of irradiating wave E and the screening field produced by charge accumulation near the edge. [ 19,23,24 ] As a result, the component at the edge differs from but . The Boltzmann approach is valid for the classical range of the radiation frequencies, i.e., , where is the mean kinetic energy of electrons and ℏ is the reduced Planck constant.…”

Grating Metamaterials Based on CdTe/CdMgTe Quantum Wells as Terahertz Detectors for High Magnetic Field Applications

“…On the other hand, we would like to stress that applicability of Equation (A4) must be limited since recent analitical considerations [41,42] show that this is rather the width of the metallic stripe, not the period of the grating, which determines the dispersion relation in a partially gated 2DEG.…”