R. G. Herb Condensed Matter Seminars |
Events on Thursday, October 26th, 2023
- First-Principles Many-Body Theory and Quantum Dynamics for Solid-State Materials
- Time: 10:00 am
- Place: 5310 Chamberlin
- Speaker: Yuan Ping, UW-Madison
- Abstract: Stable, scalable, and reliable quantum information science (QIS) is poised to revolutionize human well-being through quantum computation, communication and sensing. In this talk, I will show our recent development on first-principles computational platforms to study quantum coherence and optical readout as critical processes in QIS and spintronics in solid-state materials, by combining first-principles many-body theory and open quantum dynamics.
First, we will show how we reliably predict energetics, electronic and optical properties of spin defects and their host two-dimensional materials from first-principles many-body theory, which accurately describes highly anisotropic dielectric screening and strong many-body interactions. In particular, we will show how we predict spin-dependent optical contrast for information readout of spin qubits by computing exciton radiative and phonon-assisted nonradiative as well as spin-orbit induced intersystem crossing rates from first-principles.
Next, we will introduce our recently developed real-time density-matrix dynamics approach with first-principles electron-electron, electron-phonon, electron-impurity scatterings and self-consistent spin-orbit coupling, which can accurately predict spin and carrier lifetime and pump-probe Kerr-rotation signatures for general solids. As an example, we will show our theoretical prediction on Dirac materials under electric field to realize spin-valley locking with extremely long spin lifetime and spin diffusion length, and distinct dependence on electron-phonon couplings in spin and carrier relaxation in halide perovskites. This theoretical and computational development is critical for designing new materials promising in quantum-information science and spintronics applications. - Host: Alex Levchenko