Acoustoelectric effects in very high-mobility $p$-SiGe/Ge/SiGe heterostructure

Abstract

Measurement results of the acoustoelectric effects (surface acoustic waves (SAW) attenuation and velocity) in a high-mobility $p$-SiGe/Ge/SiGe structure are presented. The structure was LEPECVD grown with a two dimensional (2D) channel buried in the strained Ge layer. The measurements were performed as a function of temperature (1.5 - 4.2 K) and magnetic field (up to 8.4 T) at different SAW intensities at frequencies 28 and 87 MHz. Shubnikov-de Haas-like oscillations of both SAW attenuation and the velocity change have been observed. Hole density and mobility, effective mass, quantum and transport relaxation times, as well as the Dingle temperature were measured with a method free of electric contacts. The effect of heating of the 2D hole gas by the electric field of the SAW was investigated. Energy relaxation time ${\tau }_{\epsilon }$ and the deformation potential constant determined.

arXiv comment5 pages, 7 figures, 1 table

References in corpus (2)

• High-frequency hopping conductivity in the quantum Hall effect regime: Acoustical studies
• Electron localization in sound absorption oscillations in the quantum Hall effect regime

Cited by in corpus (5)

• Effective g factor of 2D holes in strained Ge quantum wells
• Acoustic Studies of AC Conductivity Mechanisms in $n$-GaAs/AlGaAs in the Integer and Fractional Quantum Hall Effect Regime
• Contactless Measurement of AC Conductance in Quantum Hall Structures
• Acoustoelectric effects in very high-mobility $p$-SiGe/Ge/SiGe heterostructure at low temperatures in high magnetic fields
• In-plane magnetic field effect on hole cyclotron mass and $g_z$ factor in high-mobility SiGe/Ge/SiGe structures