Large Magnetoresistance of a Dilute $p$-Si/SiGe/Si Quantum Well in a Parallel Magnetic Field

Abstract

We report the results of an experimental study of the magnetoresistance ${\rho }_{xx}$ in two samples of $p$-Si/SiGe/Si with low carrier concentrations $p$=8.2$\times 10^{10}$ cm${}^{-2}$ and $p$=2$\times 10^{11}$ cm${}^{-2}$. The research was performed in the temperature range of 0.3-2 K in the magnetic fields of up to 18 T, parallel to the two-dimensional (2D) channel plane at two orientations of the in-plane magnetic field $B_{\parallel }$ against the current $I$: $B_{\parallel }\perp I$ and $B_{\parallel }\parallel I$. In the sample with the lowest density in the magnetic field range of 0-7.2 T the temperature dependence of ${\rho }_{xx}$ demonstrates the metallic characteristics ($d{\rho }_{xx}/dT>$0). However, at $B_{\parallel }$ =7.2 T the derivative $d{\rho }_{xx}/dT$ reverses the sign. Moreover, the resistance depends on the current orientation with respect to the in-plane magnetic field. At $B_{\parallel }\cong$ 13 T there is a transition from the dependence $\ln (\Delta {\rho }_{xx}/{\rho }_0)\propto B_{\parallel }^2$ to the dependence $\ln (\Delta {\rho }_{xx}/{\rho }_0)\propto B_{\parallel }$. The observed effects can be explained by the influence of the in-plane magnetic field on the orbital motion of the charge carriers in the quasi-2D system.

revised: included AC conductivity experiments to study the role of localized state in transport; total 6 pages, 7 figures. Accepted PRB; to appear vol.79, Issue 20

References in corpus (12)

• Interaction corrections at intermediate temperatures: I. Longitudinal conductivity and kinetic equation
• In-plane magnetic field-induced spin polarization and transition to insulating behavior in two-dimensional hole systems
• Spin polarization and g-factor of a dilute GaAs two-dimensional electron system
• Phase separation in the two-dimensional electron liquid in MOSFETs
• Spin polarization and metallic behavior of a silicon two-dimensional electron system
• Two-dimensional metal-insulator transition and in-plane magnetoresistance in a high mobility strained Si quantum well
• The metallic resistance of a dilute two-dimensional hole gas in a GaAs quantum well: two-phase separation at finite temperature?
• Two-dimensional metal in a parallel magnetic field
• Spin polarization induced tenfold magneto-resistivity of highly metallic 2D holes in a narrow GaAs quantum well
• Conductivity of a spin-polarized two-dimensional electron liquid in the ballistic regime
• Magnetotransport in low-density $p$-Si/SiGe heterostructures: From metal through hopping insulator to Wigner glass
• Spin polarization and transition from metallic to insulating behavior in 2D systems

Cited by in corpus (6)

• Effects of Spin Polarization in the HgTe Quantum Well
• Magnetoresistivity and Acoustoelectronic Effects in a Tilted Magnetic Field in $p$-Si/SiGe/Si Structures with an Anisotropic $g$ Factor
• Quantum-Classical Crossover and Apparent Metal-Insulator Transition in a Weakly Interacting 2D Fermi Liquid
• In-plane magnetic field dependence of cyclotron relaxation time in a Si two-dimensional electron system
• Magnetoresistance in Dilute $p$-Si/SiGe in Parallel and Tilted Magnetic Fields
• Magnetoresistivity in a Tilted Magnetic Field in p-Si/SiGe/Si Heterostructures with an Anisotropic g-Factor: Part II