相关论文: Phonon Hall viscosity from phonon-spinon interacti…
Exact diagonalization calculations show a continuous transition from delocalized to small polaron behavior as a function of intersite electron-lattice coupling. A transition, found previously at Hartree-Fock level [Yonemitsu et al., Phys.…
We present a study of the thermal Hall effect in the extended Heisenberg model with $XXZ$ anisotropy in the kagome lattice. This model has the particularity that, in the classical case, and for a broad region in parameter space, an external…
We show that a quantum phase transition can occur in a phonon system in the presence of dislocations. Due to the competing nature between the topological protection of the dislocation and anharmonicity, phonons can reach a quantum critical…
We review the theories of a few quantum phase transitions in two-dimensional correlated electron systems and discuss their application to the cuprate high temperature superconductors. The coupled-ladder antiferromagnet displays a transition…
We have measured the magnetoresistance of a very low density and an extremely high quality two-dimensional hole system. With increasing magnetic field applied perpendicularly to the sample we observe the sequence of insulating, $\nu=1/3$…
The recent report of a half-quantized thermal Hall effect in the Kitaev material $\alpha$-RuCl$_3$ has sparked a strong debate on whether it is generated by Majorana fermion edge currents or whether other more conventional mechanisms…
Based on an effective QCD Lagrangian we discuss the properties of charge density fluctuations in the vicinity of chiral phase transition. We explore thermodynamics in the presence of spinodal phase separation. We show that appearance of…
The application of weak electric fields (<~ 100 V/cm) is found to dramatically enhance the lattice thermal conductivity of the antiferromagnetic (AF) insulator CaMnO(3) over a broad range of temperature about the Neel ordering point (125…
The intermediate valence (IV) compound YbAl$_3$ exhibits nonintegral valence (Yb 4$f^{14-n_f}$ (5d6s)$^z$ where z = 2+n$_f$ = 2.75) in a moderately heavy (m* = 20-30me) ground state with a large Kondo temperature (T$_K$ ~ 500-600K). We have…
A quantum spin liquid (QSL) is an exotic insulating phase with emergent gauge fields and fractionalized excitations. However, the unambiguous demonstration of the existence of a QSL in a "non-engineered" microscopic model (or in any…
We develop a theory for the thermal Hall coefficient in a spin-$\frac{1}{2}$ system on a strip of Kagome lattice, where a chiral spin-interaction term is present. To this end, we model the Kagome strip as a three-leg $XXZ$ spin-ladder, and…
We present computations of the thermal Hall coefficient of phonons scattering off a defect with multiple energy levels. Using a microscopic formulation based on the Kubo formula, we find that the leading contribution perturbative in the…
Two-dimensional (2D) magnetic systems possess versatile magnetic order and can host tunable magnons carrying spin angular momenta. Recent advances show angular momentum can also be carried by lattice vibrations in the form of chiral…
We report charge and heat transport studies in copper-intercalated topological insulator Bi$_2$Se$_3$ hybrid devices. Measured conductivity shows impact of quantum corrections, electron-electron and electron-phonon interactions. Our shot…
I construct a simple model to demonstrate that when the many-electron quantum state of a material is near a quantum phase transition and the vibrational motion of a phonon explores the potential energy surface near the transition point,…
The dynamics of magnetic moments coupled to phonons is of great interest for understanding spin transport in solids as well as for our ability to control magnetism via tailored phonon modes. For spin $S > 1/2$, spin-orbit coupling permits…
Spin orbit coupling changes graphene, in principle, into a two-dimensional topological insulator, also known as quantum spin Hall insulator. One of the expected consequences is the existence of spin-filtered edge states that carry…
Using a controlled analytic non-perturbative treatment, that accounts for the quantum nature of the phonons, we derive a model that generically describes cooperative breathing-mode at strong electron-phonon interaction in one-band…
Paramagnetic defects in diamond and hexagonal boron nitride possess a unique combination of spin and optical properties that make them prototypical solid-state qubits. Despite the coherence of these spin qubits being critically limited by…
We describe the spin dynamics of an arbitrary localized impurity in an insulating two dimensional antiferromagnet, across the host transition from a paramagnet with a spin gap to a Neel state. The impurity spin susceptibility has a…