Quantum phase transition in ultrahigh mobility SiGe/Si/SiGe two-dimensional electron system

Abstract

The metal-insulator transition (MIT) is an exceptional test bed for studying strong electron correlations in two dimensions in the presence of disorder. In the present study, it is found that in contrast to previous experiments on lower-mobility samples, in ultra-high mobility SiGe/Si/SiGe quantum wells the critical electron density, $n_{\text{c}}$, of the MIT becomes smaller than the density, $n_{\text{m}}$, where the effective mass at the Fermi level tends to diverge. Near the topological phase transition expected at $n_{\text{m}}$, the metallic temperature dependence of the resistance should be strengthened, which is consistent with the experimental observation of more than an order of magnitude resistance drop with decreasing temperature below $\sim 1$ K.

arXiv commentMisprints corrected. As published

References in corpus (19)

• Possible Metal/Insulator Transition at B=0 in Two Dimensions
• Interaction corrections at intermediate temperatures: I. Longitudinal conductivity and kinetic equation
• Metal-Insulator Transition in Disordered Two-Dimensional Electron Systems
• Transport in strongly correlated two dimensional electron fluids
• Sharp increase of the effective mass near the critical density in a metallic 2D electron system
• Challenges and opportunities of ZnO-related single crystalline heterostructures
• Dilute electron gas near the metal-insulator transition in two dimensions
• Global phase diagram for the quantum Hall effect: An experimental picture
• Coulomb Correlations and the Wigner-Mott Transition
• Metal-insulator transition in a 2D electron gas: Equivalence of two approaches for determining the critical point
• Critical Behavior of a Strongly Interacting 2D Electron System
• Ultra-high mobility two-dimensional electron gas in a SiGe/Si/SiGe quantum well
• Transport evidence for a sliding two-dimensional quantum electron solid
• Indication of band flattening at the Fermi level in a strongly correlated electron system
• Strongly enhanced effective mass in dilute two-dimensional electron systems: System-independent origin
• The energy scale behind the metallic behaviors in low-density Si-MOSFETs
• Connecting the Reentrant Insulating Phase and the Zero Field Metal-Insulator Transition in a 2D Hole System
• Spin polarization and exchange-correlation effects in transport properties of two-dimensional electron systems in silicon
• Fractional Quantum Hall Effect in SiGe/Si/SiGe Quantum Wells in Weak Quantizing Magnetic Fields

Cited by in corpus (19)

• Recent developments in the field of the metal-insulator transition in two dimensions
• Metal-insulator transition and low-density phases in a strongly-interacting two-dimensional electron system
• Density-tuned effective metal-insulator transitions in 2D semiconductor layers: Anderson localization or Wigner crystallization
• Two-dimensional system of strongly interacting electrons in silicon (100) structures
• Metallic state in a strongly interacting spinless two-valley electron system in two dimensions
• How to recognize the universal aspects of Mott criticality?
• Spin independence of the strongly enhanced effective mass in ultra-clean SiGe/Si/SiGe two-dimensional electron system
• Manifestation of strong correlations in transport in ultra-clean SiGe/Si/SiGe quantum wells
• Collective depinning and sliding of a quantum Wigner solid in a 2D electron system
• Metal-insulator transition in the disordered Hubbard model of the Lieb lattice
• Valley effects on the fractions in an ultrahigh mobility SiGe/Si/SiGe two-dimensional electron system
• Triple-top-gate technique for studying the strongly interacting 2D electron systems in heterostructures
• Spin effect on the low-temperature resistivity maximum in a strongly interacting 2D electron system
• Conductivity bound of the strongly interacting and disordered graphene from gauge/gravity duality
• Band Flattening and Landau Level Merging in Strongly-Correlated Two-Dimensional Electron Systems
• Stabilization of a two-dimensional quantum electron solid in perpendicular magnetic fields
• Microscopic Mechanism of Pair-, Charge- and Spin-Density-Wave Instabilities in Interacting D-Dimensional Fermi Liquids
• Spin and valley effects on the quantum phase transition in two dimensions
• Universal transport at Lifshitz metal-insulator transitions in two dimensions