Speaker: Prof. Liu Qian

Time: 15:00-16:00 p.m., May 12, 2023, GMT+8

Venue: Scan the QR code to enter the online channel


Abstract:

I will present a world view for electrons in crystals based the semiclassical dynamics and describe how the Berry curvatures modify the thermodynamic andtransport properties. l will then extend this point ofview to spacetime crystals by in.troducing the concept of an event wavepacket, the quantum version of the classicaevent point in spacetime. I will also describe spatial and temporal deformation, firstin 3d crystals, using a geodynamic language, and obtain Hall viscosity, flexsoelectricand flexsomagnetic responses. When the results are extended to 4d spacetime crystals, the geodynamics becomes greatly simplified andunified, allowing a fresh lookof table-top general relativity.

Biography:

Qian Niu is a Distinguished Chair Professor at the University ofScience and Technology of China. He obtained his B.S.from PekingUniversity in 1981 and his Ph.D.in physics from the University ofWashington, Seattle, in 1985. After completing postdoc studies at theUniversity of llinois and the University of California, Santa Barbara, hejoined the University of Texas at Austin as an Assistant Professor in1990. He was appointed as the Trull Centennial Chair in Physics in2001 and became the Sid W. Richardson Foundation Regents Chair inPhysics at the University of Texas at Austin in 2018. Prof. Niu has madefoundational contributions to the theories of quantum Hall effects, qua-sicrystals, ultracold atoms, spin transport, and graphene materials, withan emphasis on topological and geometric phase effects in quantumtransport. He has published more than 280 peer-reviewed papers, in-cluding 81 in Physical Review Letters, and has over 29000 citationswith an H index of 77). Prof. Niu is also a Fellow of the American Phys-cal Society.

Source: School of Physics