CENTER FOR QUANTUM MATERIALS AND CONDENSED MATTER PHYSICS SEMINARS

NEWS: The CQM Distinguished Lecture series has been established  in the Fall of 2015 to bring to Stony Brook University the renown experts in the physics of quantum matter.

The lectures in this series will attract a broad audience of physicists from SBU and BNL,
and SBU graduate students.

December 2019 – April 2020

Dec
6
Fri
Justin Wilson (Rutgers)
Dec 6 @ 1:30 pm – 2:30 pm

Title: Incommensurate transitions and twist disorder in microscopic models of twisted bilayer graphene

Abstract: Recent experiments in twisted bilayer graphene have set off a flurry of work due to the observation of purportedly correlated phases at the so-called “magic-angle.” However, the current models in the literature for magic-angle graphene suffer from two flaws: they assume commensurate twist angles and have great difficulty modeling the exact experimental setup where patches of different twist angles appear (“twist disorder”). We introduce and study a family of microscopic models that begins to address these concerns. In these models, the twist angle enters as a free parameter in real space. We can use this to simulate both incommensurate effects and disorder effects. We find that incommensuration leads to an Anderson-like delocalization transition in momentum space. The result is a small metallic phase at the “magic-angle” (that we speculate is unstable to correlated phases). We further study twist-disorder effects and find that while the minibandwidth is renormalized substantially, the Fermi velocity is not significantly altered.

Host: Jen Cano

Dec
13
Fri
Navaneetha K. Ravichandran (Boston College)
Dec 13 @ 1:30 pm – 2:30 pm

host: Phil

Jan
31
Fri
John Tranquada (BNL)
Jan 31 @ 1:30 pm – 2:30 pm

host: Phil

Feb
7
Fri
Keji Lai (UT Austin)
Feb 7 @ 1:30 pm – 2:30 pm

Title: Microwave Nano-Imaging

Host: Mengkun

 
Feb
21
Fri
Practice March Meeting talks for students
Feb 21 @ 1:30 pm – 2:30 pm

Host: Jen

Mar
6
Fri
No seminar: March Meeting
Mar 6 @ 1:30 pm – 2:30 pm
Mar
13
Fri
Jigang Wang (ISU)
Mar 13 @ 2:30 pm – 3:30 pm

title: Ultrafast magnetism

host: Mengkun

Mar
20
Fri
No seminar: Spring Break
Mar 20 @ 1:30 pm – 2:30 pm
Mar
27
Fri
Manuel Zingl (Flatiron CCQ)
Mar 27 @ 1:30 pm – 2:30 pm

Title: TBD

Host: Cyrus Dreyer

Apr
3
Fri
Xiaoji Xu (Lehigh)
Apr 3 @ 1:30 pm – 2:30 pm

title: Novel optical probe scanning method

host: Mengkun