Nonmagnetic Impurity Effect of the S=1/2 Spin Ladder System (pipdH)_2Cu_{1-x}Zn_xBr_4

TL;DR

This study synthesizes and characterizes a nonmagnetic impurity-doped S=1/2 spin ladder system, revealing how Zn doping influences magnetic properties and the spin gap.

Contribution

It provides new insights into how nonmagnetic impurities affect the magnetic behavior and spin gap in S=1/2 spin ladder systems.

Findings

Zn doping decreases the spin gap and Curie constants.

The system maintains a similar crystal structure to the pure compound.

Magnetic susceptibility shows a broad maximum indicating low-dimensionality.

Abstract

We report the synthesis and the magnetic susceptibility of (pipdH)2Cu1-xZnxBr4, which is a nonmagnetic impurity-doped S=1/2 spin ladder system. The samples were synthesized from a solution by using a slow evaporation method. Samples were confirmed to be in a single phase and to have the same crystal structure as the pure system (pipdH)2CuBr4 by using X-ray diffraction measurements. To check the magnetic properties, we performed magnetic susceptibility and magnetization measurements with a SQUID magnetometer. A plot of the inverse magnetic susceptibility indicates the presence of dominant antiferromagnetic coupling. The magnetic susceptibility shows a broad maximum due to low dimensionality and a spin gap behavior related to the two-leg spin ladder at low temperature. The spin gap and the Curie constants of Zn-doped samples, as estimated from an analysis of the magnetic susceptibility, monotonically decrease as the Zn concentration decreases. A nonmagnetic impurity of S=1/2 spin ladder system affects the spin gap.