Colloquia and Events

During the academic year, the Department hosts a weekly colloquium series which features speakers from both academia and industry.  This semester (Fall 2018) the colloquia take place on Thursdays from 3:15-4:30 pm in BIOS 335.  Refreshments are served at 3:15 pm and talks begin at 3:30 pm.

This week's colloquium

"Advances in Computing Charge Carrier Dynamics in Materials from First Principles"
Prof. Marco Bernardi, Caltech
Thursday, Nov. 29, 3:15 pm in BIOS 335

Calculations of charge transport and ultrafast dynamics have relied on heuristic approaches for the past several decades. Recent progress in combining density functional theory and related methods with kinetic equations, such as the Boltzmann transport equation (BTE), are enabling spectacular advances in computing carrier dynamics in materials from first principles. A special role is played by the interaction between charge carriers and lattice vibrations, also known as the electron-phonon (e-ph) interaction, which dominates carrier dynamics near room temperature and at energies within a few eV of the band gap. We will discuss our recently developed methods to compute e-ph scattering processes from first principles, and show how these developments enable accurate calculations of charge transport and ultrafast dynamics in materials, including: 1) Accurate calculations of the electron mobility, leading to new insight into charge transport in polar semiconductors, perovskite oxides, and organic materials. We will also touch briefly on the computation of polaronic states using the cumulant method. 2) The ultrafast dynamics of excited (so-called “hot”) carriers, with application to ultrafast spectroscopy and optoelectronics. A new parallel algorithm to propagate in time the BTE for excited electrons and coupled electrons and phonons will also be presented.

 

Upcoming colloquia

None until Spring 2019!

Previous colloquia

Nov. 15: Prof. Olaseni Sode, Cal State LA, "Exploring the electronic and vibrational structure of carbon dioxide"

Nov. 8: Prof. Zhongbo Kang, UCLA, "Quantum tomography of a proton"

Nov. 1: Prof. Ximin He, UCLA, "Bioinspired Dynamic Material Systems based on Smart Hydrogels: Sensing, Sorting, and Harvesting"

Oct. 25: Dr. Coral Wheeler, Caltech, "Be it therefore resolved: simulating dwarf galaxies at the high resolution limit"

Oct. 18: Prof. Breanna Binder, Cal Poly Pomona, "SN2010da: From Supernova Impostor to Ultraluminous X-ray Source"

Oct. 11: Prof. Anna Bezryadina, CSU Northridge, "Optical trapping and manipulation of bacteria"

Oct. 4: Prof. Wylie Ahmed, CSU Fullerton, "Active mechanics and forces that keep our cells alive" 

Sept. 27: Prof. Eli Levenson-Falk, USC, "Fleas on Schrödinger's Cat: Decoherence in Superconducting Quantum Circuits"

Sept. 20: Arabi Seshappan, Cal State LA, "CeBOx (B=La, Mn, Co, Fe) as potential catalysts for thermochemical water splitting reactions"

Sept. 13: Marc Ong, Cal State LA, "Applications of machine learning in physics and chemistry"

Sept. 6: Prof. Peter Zhao, Cal State LA, "Polaronic high-temperature superconductivity in cuprates, bismuthates, and pnictides"

May 3: Prof. Christoph Haselwandter, USC, "Collective phenomena in cell membranes"

April 26: Dr. Yuval Baum, Caltech, "Current at a distance and resonant transparency in Weyl semimetals"

April 19: Prof. Jayakanth Ravichandran, USC, "Shining Light on Perovskite Chalcogenides: Semiconductors for Visible to Infrared Optoelectronics"

This list will be rebuilt shortly!  (We had a little accident...)