Off-diagonal exchange-induced transverse and field-induced spin-flop order in the diluted metamagnet

$\chem{Fe_{0.85}Mg_{0.15}Br_2}$

Author： Kleemann W. Aruga Katori H. Kato T. Binek Ch. Katsumata K.

E-ISSN： 1286-4854|55|5|732-738

ISSN： 0295-5075

Source： EPL (EUROPHYSICS LETTERS), Vol.55, Iss.5, 2010-03, pp. : 732-738

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Specific heat and Faraday rotation magnetometry were used todetermine the axial magnetic phase diagram of the dilutehexagonal antiferromagnet $\chem{Fe_{0.85}Mg_{0.15}Br_2}$.In contrast to metamagnetic pure $\chem{FeBr_2}$, the first-order lineof transverse phase transitions, $H_1(T)$, is disconnected withthe antiferro-to-paramagnetic phase line $H_\ab{c}(T)$ and extendsdown to $H_\ab{t}=0$ at $T_\ab{t}\approx8.7$ $\un{K}$. This isattributed to symmetric off-diagonal exchange in the presence ofstructural disorder. Moreover, a spin-flop phase emerges beyond$H_\ab{c}(T)$ up to a bicritical point ($T_\ab{b}\approx9.3$ $\un{K}$,$\mu_0H_\ab{b} \approx 1.3$ $\un{T}$).