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Magnetic-Field Induced Gap in One-Dimensional Antiferromagnet KCuGaF$_6$

R. Morisaki·T. Ono·H. Tanaka·H. Uekusa
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Abstract

Magnetic susceptibility and specific heat measurements in magnetic fields were performed on an $S=1/2$ one-dimensional antiferromagnet KCuGaF$_6$. Exchange interaction was evaluated as $J/k_{\rm B}\simeq 100$ K. However, no magnetic ordering was observed down to 0.46 K. It was found that an applied magnetic field induces a staggered magnetic susceptibility obeying the Curie law and an excitation gap, both of which should be attributed to the antisymmetric interaction of the Dzyaloshinsky-Moriya type and/or the staggered $g$-tensor. With increasing magnetic field $H$, the gap increases almost in proportion to $H^{2/3}$.

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R. Morisaki, T. Ono, H. Tanaka, H. Uekusa. 2006-07-19. Magnetic-Field Induced Gap in One-Dimensional Antiferromagnet KCuGaF$_6$. https://doi.org/10.1088/1742-6596%2F51%2F1%2F041

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