Potassium-Doped Para-Terphenyl: Structure, Electrical Transport Properties and Possible Signatures of a Superconducting Transition

TL;DR

This study synthesizes potassium-doped p-terphenyl, revealing a significant resistivity drop below 90 K that suggests possible high-temperature superconductivity in this organic material, with a focus on structural and electrical properties.

Contribution

It provides new experimental evidence of a broad superconducting transition in potassium-doped p-terphenyl, using synthesis, Raman, and resistivity measurements, highlighting its potential as a high-Tc organic superconductor.

Findings

Resistivity drops over 4 orders of magnitude below 90 K.

Broad transition possibly due to granular nature of the material.

Evidence suggests potential high-temperature superconductivity.

Abstract

Preliminary evidence for the occurrence of high-Tc superconductivity in alkali-doped organic materials, such as potassium-doped p-terphenyl (KPT), were recently obtained by magnetic susceptibility measurements and by the opening of a large superconducting gap as measured by ARPES and STM techniques. In this work, KPT samples have been synthesized by a chemical method and characterized by low-temperature Raman scattering and resistivity measurements. Here, we report the occurrence of a resistivity drop of more than 4 orders of magnitude at low temperatures in KPT samples in the form of compressed powder. This fact was interpreted as a possible sign of a broad superconducting transition taking place below 90 K in granular KPT. The granular nature of the KPT system appears to be also related to the 20 K broadening of the resistivity drop around the critical temperature.