Qiu, R.L.J.; Liu, C.-W.; Liu, S.; Gao, X.P.A. New Reentrant Insulating Phases in Strongly Interacting 2D Systems with Low Disorder. Appl. Sci.2018, 8, 1909.
Qiu, R.L.J.; Liu, C.-W.; Liu, S.; Gao, X.P.A. New Reentrant Insulating Phases in Strongly Interacting 2D Systems with Low Disorder. Appl. Sci. 2018, 8, 1909.
The apparent metal-insulator transition (MIT) in two-dimension (2D) was discovered by Kravchenko et al.  more than two decades ago in strongly interacting 2D electrons residing in a Si-metal-oxide-semiconductor field-effect transistor (Si-MOSFET). Its origin remains unresolved. Recently, low magnetic field reentrant insulating phases (RIPs), which dwell between the zero-field (B=0) metallic state and the integer quantum Hall (QH) states where the Landau-level filling factor υ > 1, have been observed in strongly correlated 2D GaAs hole systems with large interaction parameter rs (~20-40) and high purity. A new complex phase diagram was proposed, which includes zero field MIT, low magnetic field RIPs, integer QH states, fractional QH states, high field RIPs and insulating phases (HFIPs) with υ < 1 in which the insulating phases are explained by the formation of Wigner crystal. Furthermore, evidences of new intermediate phases were reported. All contribute to the further understandings of the puzzle. This review article serves the purpose of summarizing those recent experimental findings and theoretical endeavors, to foster future research efforts.
metal-insulator transitions; electronic transport in interface structures; quantum hall effects
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