Probing spin susceptibility of a correlated two-dimensional electron system by transport and magnetization measurements

Article

关键词: METAL-INSULATOR-TRANSITION;    INVERSION-LAYER;    QUANTIZED HALL;    2D ELECTRONS;    PHASE;    DENSITY;    LIQUID;    OSCILLATIONS;    DISORDER;    BEHAVIOR;   

DOI  :  10.1103/PhysRevB.98.155109

来源: SCIE

【 摘 要 】

We report temperature and density dependences of the spin susceptibility of strongly interacting electrons in Si inversion layers. We measured (i) the itinerant electron susceptibility chi* from the Shubnikov-de Haas oscillations in crossed magnetic fields and (ii) thermodynamic susceptibility chi(T) sensitive to all the electrons in the layer. Both chi* and chi(T) are strongly enhanced with lowering the electron density in the metallic phase. However, there is no sign of divergency of either quantity at the density of the metal-insulator transition n(c). Moreover, the value of chi(T), which can be measured across the transition down to very low densities deep in the insulating phase, increases with density at n < n(c), as expected. In the absence of magnetic field, we found the temperature dependence of chi* to be consistent with Fermi-liquid-based predictions, and to be much weaker than the power law predicted by non-Fermi-liquid models. We attribute a much stronger temperature dependence of chi(T) to localized spin droplets. In strong enough in-plane magnetic field, we found the temperature dependence of chi* to be stronger than that expected for the Fermi liquid interaction corrections.

【 授权许可】

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