Search for superfluidity in supercooled liquid parahydrogen

TL;DR

This study uses quantum Monte Carlo simulations to investigate superfluidity in supercooled liquid parahydrogen, finding no evidence of superfluidity due to the large hard core diameter of interactions, challenging previous assumptions.

Contribution

It demonstrates that the large hard core diameter, not the well depth, prevents superfluidity in parahydrogen, providing new insight into its quantum behavior.

Findings

No superfluidity observed down to 0.25 K

Particle exchanges are strongly suppressed

Hard core diameter hinders superfluidity

Abstract

The possible superfluid transition of supercooled liquid parahydrogen is investigated by quantum Monte Carlo simulations. The cooling protocol adopted here allows for the investigation of a fluid phase down to a temperature T=0.25 K. No evidence of superfluidity is found, as exchanges of identical particles are strongly suppressed even at the lowest temperature. Is shown that, contrary to a commonly held belief, it is not the well depth of the pair-wise interaction but rather its relatively large hard core diameter that physically hinders superfluidity in parahydrogen.