LASSP & AEP Seminar by Benjamin Feldman (Stanford University)

Benjamin Feldman
Assistant Professor of Physics
Stanford University

Thermodynamic sensing of correlated phases in twisted transition metal dichalcogenides

The twist angle between adjacent two-dimensional layers provides a powerful tuning knob to tailor electronic properties. When two materials have similar lattice constants and low interlayer twist, a moiré superlattice develops and can lead to flat electronic bands which host a variety of interaction-driven phases. In this talk, I will describe electronic compressibility measurements with a scanning single-electron transistor that reveal novel ground states and excitations in twisted semiconducting transition metal dichalcogenides. In twisted double bilayer WSe₂, probing the energy gaps of the correlated insulating states as a function of magnetic and electric field allows us to determine their spin and valley character as well as identify itinerant spin polaron excitations. I will also present recent measurements of a device with a long moiré wavelength which reveal an intricate phase diagram of correlated states as a function of carrier density and magnetic field. I will discuss how these findings reflect the interplay between electronic interactions and the nature of the underlying moiré bands.

Hosted by Katja Nowack and Valla Fatemi

Pizza served starting at 12:10 p.m.
Please bring your own beverage

For those who cannot attend in person but would like to see the seminar, livestream only will be available via Zoom:
https://cornell.zoom.us/j/98722799978?pwd=OEdYdGpWYjVuSHh2Ry82NGw3T3ZZQT09
Webinar ID: 987 2279 9978
Passcode: 8235