Spatially resolved Raman scattering from hot acoustic and optic plasmons

Abstract

A two-dimensional electron gas drifting under a lateral bias is also heated, and the drift and heating have dramatic effects on its collective plasmon modes. A low-energy feature is observed in polarized Raman scattering in addition to the usual intrasubband plasmon mode, and disperses linearly with in-plane wave vector. Large variations in the Raman intensities and energies of the intrasubband plasmon and the low-energy feature are observed with position along the drift channel, together with variations in the electron temperature and in the integrated photoluminescence intensity. These effects are discussed in terms of a simple model involving a second sheet of electrons near the current injection contact; the low-energy mode is ascribed to an additional acoustic plasmon mode arising from this double-electron sheet geometry.

Synthesizing Coulombic superconductivity in van der Waals bilayers

“…Optics -The acoustic plasmon is essentially a longitudinal mode involving the relative charge oscillations on the two layers. As such it can be measured using Raman spectroscopy, as demonstrated in GaAs quantum wells [59][60][61].…”

Theory of Detection of Terahertz Radiation in Hybrid Plasmonic Structures with Drifting Electron Gas

“…where ( ) sc | 0=0 is the plasmon frequency in the absence of the electron drift. In this model, the splitting is determined by the Doppler shift, 0 (see, e.g., [4,46,47]). For the estimations, we used the expression of sc ( )| 0=0 in the case of 2D plasmons gated by the ideal metallic mirror:…”

Instability of plasma vibrations in a wide parabolic GaAs/AlGaAs quantum well caused by plasmon-assisted tunnelling. A possible mechanism for generation and amplification of far-infrared radiation

“…Direct current-driven plasma instabilities in GaAs/AlGaAs artificial heterostructures (twodimensional layers and superlattices) have attracted much attention due to the interesting fundamental physics involved and possible applications for generation and amplification of infrared radiation (see for example [1][2][3][4][5][6][7]). In particular much work has been done on the interaction of direct current flowing along a two-dimensional layer with plasma waves in the same (or a neighbouring) layer [1][2][3][4][5][6]. This interaction can result in the growth of the plasma wave magnitude due to the energy transfer from direct current to plasma waves.…”