Magnetization process of the S = 1/2 two-leg organic spin-ladder compound BIP-BNO

TL;DR

This study investigates the magnetization behavior of the organic S=1/2 two-leg spin-ladder compound BIP-BNO under high magnetic fields, confirming the Heisenberg model with quantum Monte Carlo simulations and estimating key exchange constants.

Contribution

It provides the first detailed experimental and theoretical analysis of BIP-BNO's magnetization process, validating the spin-ladder model and estimating exchange interactions.

Findings

Magnetization saturates at 76 T.

Exchange constants estimated as J(rung)/kB = 65.7 K and J(leg)/kB = 14.1 K.

Model accurately reproduces experimental magnetization curve.

Abstract

We have measured the magnetization of the organic compound BIP-BNO (3,5'-bis(N-tert-butylaminoxyl)-3',5-dibromobiphenyl) up to 76 T where the magnetization is saturated. The S = 1/2 antiferromagnetic Heisenberg two-leg spin-ladder model accounts for the obtained experimental data regarding the magnetization curve, which is clarified using the quantum Monte Carlo method. The exchange constants on the rung and the side rail of the ladder are estimated to be J(rung)/kB = 65.7 K and J(leg)/kB = 14.1 K, respectively, deeply in the strong coupling region: J(rung)/J(leg) > 1.