IQIM Postdoctoral and Graduate Student Seminar

Note: Special IQIM Seminar on Wednesday, Sept 30 at noon

Abstract: Quantum simulation with ultracold atoms is a powerful platform for understanding the microscopic foundations underlying fractional quantum Hall phases, where the interplay between particle interactions and a magnetic field gives rise to wave functions with distinctive correlations. The single-site control and imaging capabilities of a quantum gas microscope allow us to probe these correlations directly. Using artificial gauge fields and a bottom-up adiabatic ramp to the ground state, we are able to create and study quantum hall states through their characteristic correlation signatures. 

Our latest project applies this process to the Pfaffian state, an especially sought-after topological phase predicted to host features like non-abelian anyonic excitations and p-wave pairing. We prepare the state using three atoms on a 5x5 grid, and measure density correlations consistent with this pairing picture as described by the Moore-Read wave function: a pronounced suppression of local three-body correlations relative to the normal state, but a much weaker suppression of two-body correlations, representing a state where two particles form a pair that the third one avoids. We also implement a transport-style probe analogous to traditional condensed matter Hall-drift measurements by quenching the confinement and measuring the center-of-mass drift in response to a weak applied force. This drift velocity agrees with theory, establishing a proof-of-concept for connecting the properties of our small system to the larger counterparts. Together, these measurements represent an important step forward in making artificial FQH states accessible to cold atom experiments, paving the way towards engineering larger states and measuring more complicated topological observables.

Informal Pizza lunch following the talk.