Fermionization of two distinguishable fermions

TL;DR

This paper investigates the fermionization phenomenon in a two-fermion system in a 1D harmonic trap, demonstrating experimental and theoretical agreement at diverging interaction strength, and highlighting its potential for quantum simulation.

Contribution

It provides an analytic solution for two distinguishable fermions with tunable interactions and experimentally observes fermionization, advancing quantum simulation capabilities.

Findings

Good agreement between experiment and theory at diverging interaction strength.

Fermionization causes distinguishable fermions to mimic identical fermions.

Potential for simulating complex few-body quantum systems.

Abstract

In this work we study a system of two distinguishable fermions in a 1D harmonic potential. This system has the exceptional property that there is an analytic solution for arbitrary values of the interparticle interaction. We tune the interaction strength via a magnetic offset field and compare the measured properties of the system to the theoretical prediction. At the point where the interaction strength diverges, the energy and square of the wave function for two distinguishable particles are the same as for a system of two identical fermions. This is referred to as fermionization. We have observed this phenomenon by directly comparing two distinguishable fermions with diverging interaction strength with two identical fermions in the same potential. We observe good agreement between experiment and theory. By adding one or more particles our system can be used as a quantum simulator for more complex few-body systems where no theoretical solution is available.