Heat Capacity Anomaly of LSCO Cuprates with Nonmagnetic Impurity

TL;DR

This study investigates the low-temperature heat capacity of pure and Zn-doped LSCO cuprates using a novel high-precision calorimetry method, revealing a new impurity-related anomaly that differs from typical phonon behavior.

Contribution

It introduces a new high-precision calorimetry technique and reports a previously unobserved heat capacity anomaly linked to nonmagnetic impurities in LSCO cuprates.

Findings

Discovered a new heat capacity anomaly associated with Zn impurities.

Anomaly appears as a broad peak unaffected by Zn content.

Method provides equilibrium measurements unlike traditional DSC.

Abstract

The low temperature heat capacity investigations on pure(y=0) and Zn-doped La1.84Sr0.16Cu1-yZnyO4 samples have been performed in the interval of 1.8-60K by a new method of high-precision, pulsed differential calorimetry (PDC), which provides the measurements under the equilibrium conditions, in contrast to commonly used differential scanning calorimeters (DSC). For these systems a new heat capacity anomaly was observed, which is associated with Zn impurities and has the form of one wide peak. It does not show a phonon character shifts towards the higher temperatures with the increase of Zn content.