First-Principles Materials Prediction: From Sustainability to the Quantum Information Age – Prof. Yuan Ping, UCSC

First-Principles Materials Prediction: From Sustainability to the Quantum Information Age

Theory-guided materials design is vital to the advancement of sustainability and quantum information science. First-principles theory entirely based on quantum mechanics without prior input parameters is the perfect tool. In order to reliably predict exotic quantum materials and out-of-equilibrium processes, many-body physics and quantum kinetic theory are important to bridge with first-principles methods.

In this talk, I will discuss our development on theory and numerical codes on many-body perturbation theory (MBPT), for accurate prediction of optical excitation and exciton recombination1,2,3. We will discuss how we use these methods to solve  material problems in photoelectrochemical applications and predict spin qubit properties for quantum information science4,5.  In particular, we will show an example on how substrate screening affects interfacial charge transfer and exciton energies, with our recently developed technique based on MBPT that applies for arbitrarily lattice-mismatched interfaces without strain6.  

Next, I will show our recent method development on real-time open quantum dynamics with coupled spins, electrons, photons and phonons based on first-principles density-matrix approach7,8. We will discuss its important applications on understanding valley dynamics, spin transport as well as ultrafast coupled spin and carrier dynamics at finite temperature. This method will offer new and unbiased insights for spin and valley relaxation and decoherence in general systems, and determine design rules for new materials with ideal physical properties for spintronics, valleytronics, and quantum information science.

References:

• [1] F. Wu, D. Rocca, and Y. Ping, Journal of Materials Chemistry C, 7, 12891, (2019).
• [2] F. Wu, T. Smart, J. Xu, and Y. Ping, Physical Review B, 100, 081407(R) (2019).
• [3] Y. Ping, D. Rocca, and G. Galli, Chem. Soc. Rev.  42, 2437 (2013).
• [4] F. Wu, A. Galatas, R. Sundararaman, D. Rocca, and Y. Ping, Physical Review Materials, 1, 071001(R), (2017).
• [5] T. Smart, K. Li, J. Xu, and Y. Ping, “Intersystem Crossing and Exciton-Defect Coupling of Spin Defects in Hexagonal Boron Nitride”, under review,  arXiv:2009.02830 [cond-mat-mtrl-sci], (2021).
• [6] C. Guo, J. Xu, D. Rocca and Y. Ping, Physical Review B, 102, 205113, (2020). Editors’ Suggestion.
• [7] J. Xu, A. Habib, S. Kumar, F. Wu, R. Sundararaman, and Y. Ping, Nature Communications, 11, 2780, (2020).
• [8] J. Xu, A. Habib, R. Sundararaman, and Y. Ping, “Ab initio Ultrafast Spin Dynamics in Solids”, under review, arXiv: 2012.08711 [cond-mat-mtrl-sci], (2021).