Quantum Phase Transitions with the change of the internal topology.
Superconductor-Insulator Transitions in (2+1) dimensions
Dynamical Scaling under the parameter of Field, Disorder, and Topology
Nonequilibrium Phase Transitions in CDW-dynamics
Macroscopic Quantum Tunneling of Topological Defects
(Vortices, Phase Solitons of CDW, Dislocations)

Discover of NbSe3 Ring, Tube, Disk-Crystals
Discover of New Type Topological Materials
Topological Defects on the Topological Materials
Order Parameter on the Topological Materials
Knot-Crystals , Mobius Crystals
NbSe2-nanotubes

Activities

Research in my group has mainly focused on one theme: transport phenomena (of electrons, vortices, charge density wave) in systems that have disorder and/or reduced dimensionality and/or topological constrain. Examples include confined geometries (e.g., films, slabs, wires, networks, Mobius strip), multilayers, aperiodic, and disordered media. We use MBE, AFM, CVT, and FIB techniques to find new phenomena experimentally, and we often collaborate with theoretical groups. Specific problems we are studying include: dynamics of superconducting vortices in disordered media; nonlinear threshold dynamics, collapse, avalanches, and instabilities in granular and superconducting systems; magnetic and thermal properties of high-TC materials; hole dynamics and other properties of quantum antiferromagnets; phonon and electron transport in quasicrystalline and other aperiodic systems; acoustic interference, phonon localization and universal transmission fluctuations; quantum fluctuations in solids; and quantum interference due to electron motion in magnetic fields in a variety of systems (including superconducting wire networks and Josephson junction arrays). Under certain circumstances, several of these apparently unrelated systems exhibit interesting complex nonlinear dynamics when driven to the threshold of instability.

Publications and invited talks

Full list of publications and invited talks