相关论文: Novel metallic behavior in two dimensions
We have studied the resistivity, $\rho$, of a two-dimensional electron system in silicon in the temperature range 200 mK < T < 7.5 K at zero magnetic field at low electron densities, when the electron system is in the insulating regime. Our…
A novel variational method is proposed for calculating the percolation threshold, the real-space structure, and the thermodynamical compressibility of a disordered two-dimensional electron liquid. Its high accuracy is verified against prior…
Materials with reduced dimensions have been shown to host a wide variety of exotic properties and novel quantum states that often defy textbook wisdom1-5. Ferroelectric polarization and metallicity are well-known examples of mutually…
We report a detailed scaling analysis of resistivity \rho(T,n) measured for several high-mobility 2D electron systems in the vicinity of the 2D metal-insulator transition. We analyzed the data using the two parameter scaling approach and…
The apparent metal-insulator transition is observed in a high quality two-dimensional electron system (2DES) in the strained Si quantum well of a Si/Si_{1-x}Ge_x heterostructure with mobility \mu=1.9 x 10^5 cm^2/Vs at density n=1.45 x…
We explore the physics of novel fermion liquids emerging from conducting networks, where 1D metallic wires form a periodic 2D superstructure. Such structure naturally appears in marginally-twisted bilayer graphenes, moire transition metal…
We report experiment and theory on an ambipolar gate-controlled Si-vacuum field effect transistor (FET) where we study electron and hole (low-temperature 2D) transport in the same device simply by changing the external gate voltage to tune…
We present a theory of the effects of impurity scattering in d_{x^2-y^2} superconductors and their quantum disordered counterparts, based on a non-linear sigma model formulation. We show the existence, in a quasi-two-dimensional system, of…
We theoretically study transport in two-dimensional semimetals. Typically, electron and hole puddles emerge in the transport layer of these systems due to smooth fluctuations in the potential. We calculate the electric response of the…
Some of the highest-transition-temperature superconductors across various materials classes exhibit linear-in-temperature `strange metal' or `Planckian' electrical resistivities in their normal state. It is thus believed by many that this…
The gold film (mean thickness $\approx$ 3.5 nm) was condensed in high vacuum at temperature 70 K on single-crystal sapphire substrate. The transport properties of the film at low temperature reveal simultaneously indications of 1D and 2D…
Scaling down materials to an atomic-layer level produces rich physical and chemical properties as exemplified in various two-dimensional (2D) crystals extending from graphene, transition metal dichalcogenides to black phosphorous. This is…
We study charge transport across the metal-insulator crossover in the half-filled two-dimensional Hubbard model, with particular emphasis on precision control. The dynamic current-current correlation function is obtained directly in the…
The insulator-to-metal transition in dense fluid hydrogen is an essential phenomenon to understand gas giant planetary interiors and the physical and chemical behavior of highly compressed condensed matter. Using fast laser spectroscopy…
To understand complex physics of a system with strong electron electron interactions, it is ideal to control and monitor its properties while tuning an external electric field applied to the system. Indeed, complete electric field control…
We investigate the features of charge transport in a novel holographic quantum phase transition (QPT) model with two metallic phases: normal metallic and novel metallic. The scaling behaviors of direct current (DC) resistivity and thermal…
In moir\'e heterostructures, gate-tunable insulating phases driven by electronic correlations have been recently discovered. Here, we use transport measurements to characterize the gate-driven metal-insulator transitions and the metallic…
We study the universality class for localization which arises from models of non-interacting quasiparticles in disordered superconductors that have neither time-reversal nor spin-rotation symmetries. Two-dimensional systems in this…
Two recent electronic transport experiments from Columbia University and Harvard University have reported record high mobility and low channel densities in transition metal dichalcogenide (TMD) WSe$_2$ monolayers [J. Pack, et al.,…
Two-dimensional (2D) superconductivity is a fascinating phenomenon packed with rich physics and wide technological application. The vortices and their dynamics arising from classical and quantum fluctuations give rise to…