Department of Applied Physics and Materials Science - Materials Science

Materials Science Research Lecture

Wednesday April 6, 2022 4:00 PM

First-Principles Many-Body Theory and Quantum Dynamics for Materials in Quantum Information Science

Speaker: Yuan Ping, UC Santa Cruz
Location: Noyes 153 (J. Holmes Sturdivant Lecture Hall)

Webinar Link:

Webinar ID: 832 7665 2110

NOTE: At this time, in-person APhMS seminars are open to all Caltech students/staff/faculty/visitors with a valid Caltech ID. Outside community members are welcome to join our online event.


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 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 radiative and nonradiative as well as intersystem crossing kinetic processes with strong exciton-defect couplings 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 with extremely long spin lifetime and spin diffusion length. This theoretical and computational development is critical for designing new materials promising in quantum-information science, spintronics, and valleytronics applications.

More about the Speaker:

Yuan Ping received her B.Sc. degree from University of Science and Technology of China in 2007, Ph.D. from UC Davis in 2013, and materials postdoctoral fellow at Caltech in 2016. From then she is an assistant professor at UC Santa Cruz. Her research group focuses on developing first-principles many-body theory and quantum dynamics for materials applications. Ping is a recipient of Alfred Sloan Research Fellow (2022), NSF CAREER Award (2022), Air Force YIP award (2021), and ACS COMP OpenEye Award (2021).

Series Materials Research Lecture Series

Contact: Jennifer Blankenship