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arXiv · 1105.4778

Metallic Behavior of Cyclotron Relaxation Time in Two-Dimensional Systems

Ryuichi Masutomi·Kohei Sasaki·Ippei Yasuda·Akihito Sekine·Kentarou Sawano·Yasuhiro Shiraki·Tohru Okamoto
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Abstract

Cyclotron resonance of two-dimensional electrons is studied at low temperatures down to 0.4 K for a high-mobility Si/SiGe quantum well which exhibits a metallic temperature dependence of dc resistivity $ρ$. The relaxation time $τ_{\rm CR}$ shows a negative temperature dependence, which is similar to that of the transport scattering time $τ_t$ obtained from $ρ$. The ratio $τ_{\rm CR}/τ_t$ at 0.4 K increases as the electron density $N_s$ decreases, and exceeds unity when $N_s$ approaches the critical density for the metal-insulator transition.

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Ryuichi Masutomi, Kohei Sasaki, Ippei Yasuda, Akihito Sekine, Kentarou Sawano, Yasuhiro Shiraki, Tohru Okamoto. 2011-05-24. Metallic Behavior of Cyclotron Relaxation Time in Two-Dimensional Systems. https://doi.org/10.1103/physrevlett.106.196404

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