TRR 360 Seminar:

Signatures of fractional quantum Hall states in few-body systems

Cecile Repellin

Signatures of fractional quantum Hall states in few-body systems

Dr. Cecile Repellin

Université Grenoble Alpes, CNRS, LPMMC, Grenoble, France

Realizing strongly correlated topological phases of ultracold gases is a central goal for quantum gas experiments. Due to the difficulty in preparing these phases, ongoing experiments are focusing on ensembles of few atoms, and the preparation of a fractional quantum Hall state of two bosonic atoms has been achieved [1]. Beyond their preparation, the characterization of these few-body states poses a unique challenge due to their small system size. I will discuss which signatures can be used, and show that hallmark fingerprints of fractional quantum Hall phases, such as a quantized Hall conductivity [2], or chiral edge modes[3], can be extracted in few-particle systems through local density measurements.

[1] Léonard, J., Kim, S., Kwan, J. et al., Realization of a fractional quantum Hall state with ultracold atoms. Nature 619, 495–499 (2023).
[2] Repellin, C., Léonard, J. and Goldman, N., Chern insulators of few bosons in a box: Hall plateaus from center-of-mass drifts and density profiles. Phys. Rev. A 102, 063316 (2020).
[3] Binanti, F., Goldman, N., Repellin, C, Spectroscopy of edge and bulk collective modes in fractional Chern insulators. Phys. Rev. Research 6, L012054 (2024).