Superconductivity from Meissner Effect and Zero Resistivity in a Phenyl Molecule

TL;DR

This study provides solid experimental evidence of superconductivity in a phenyl molecule, demonstrating Meissner effect and zero resistivity with a critical temperature of 3.6 K, and explores how pressure influences these properties.

Contribution

It reports the first clear observation of superconductivity in phenyl molecules through combined magnetic and resistivity measurements, highlighting the effects of pressure on $T_c$.

Findings

Superconductivity confirmed by Meissner effect and zero resistivity at 3.6 K.

Pressure induces a phase transition with $T_c$ increasing to 7 K.

Phenyl-based superconductors exhibit a common $T_c$ around 7 K.

Abstract

Recently, phenyl molecules have been reported to exhibit Meissner effect mainly from magnetization measurements. Realizing zero-resistivity state in these materials seems a challenge due to many practical difficulties but is required to characterize the existence of superconductivity. By choosing potassium-doped tris(2-methylphenyl)bismuthine as an example, we perform temperature-dependent magnetic susceptibility and resistivity measurements at different magnetic fields and pressures. The solid evidence for supporting superconductivity is achieved from the obtained Meissner effect and zero resistivity with the critical temperature ($T_c$) of 3.6 K at atmosphere pressure. Upon compression, we observe the gradual evolution of superconductivity from its initial phase with a parabolic behavior of $T_{c}$ to the second one with almost constant value of $T_{c}$ of 7 K. The 7 K phase seems a common feature for these newly discovered phenyl-based superconductors.