Observation of non-Hermitian many-body skin effects in Hilbert space

TL;DR

This paper reports the first experimental observation of non-Hermitian many-body skin effects in a strongly correlated bosonic system, revealing new physical phenomena in Hilbert space through electric circuit simulations.

Contribution

It introduces the experimental simulation of non-Hermitian many-body phases and demonstrates a new type of skin effect induced by interactions in a Hilbert space setting.

Findings

Observation of non-Hermitian many-body skin states in Hilbert space

Verification via electric circuit impedance measurements

Discovery of interaction-induced skin effects in bosonic clusters

Abstract

Non-Hermiticity greatly expands existing physical laws beyond the Hermitian framework, revealing various novel phenomena with unique properties. Up to now, most exotic nonHermitian effects, such as exceptional points and non-Hermitian skin effects, are discovered in single-particle systems. The interplay between non-Hermitian and manybody correlation is expected to be a more fascinating but much less explored area. Due to the complexity of the problem, current researches in this field mainly stay at the theoretical level. The experimental observation of predicted non-Hermitian manybody phases is still a great challenging. Here, we report the first experimental simulation of strongly correlated non-Hermitian many-body system, and reveal a new type of nonHermitian many-body skin states toward effective boundaries in Hilbert space. Such an interaction-induced non-Hermitian many-body skin effect represents the aggregation of bosonic clusters with non-identical occupations in the periodic lattice. In particular, by mapping eigen-states of three correlated bosons to modes of the designed threedimensional electric circuit, non-Hermitian many-body skin effects in Hilbert space is verified by measuring the spatial impedance response. Our finding not only discloses a new physical effect in the non-Hermitian many-body system, but also suggests a flexible platform to further investigate other non-Hermitian correlated phases in experiments.