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

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 $J/k_{\mathrm{B}}\simeq 100$ 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 $H^{2/3}$.

arXiv commentSubmitted to Proceedings of Research in High Magnetic Field

References in corpus (9)

• Susceptibility of the Spin 1/2 Heisenberg Antiferromagnetic Chain
• Thermodynamics and spin gap of the Heisenberg ladder calculated by the look-ahead Lanczos algorithm
• Theory of the field-induced gap in $S=1/2$ antiferromagnetic chains
• On the Field-Induced Gap in Cu Benzoate and Other S=1/2 Antiferromagnets
• Direct Observation of Field-Induced Incommensurate Fluctuations in a One-Dimensional S=1/2 Antiferromagnet
• The spin-1/2 Heisenberg chain: thermodynamics, quantum criticality and spin-Peierls exponents
• ESR investigation on the Breather mode and the Spinon-Breather dynamical crossover in Cu Benzoate
• Excitation hierarchy of the quantum sine-Gordon spin chain in strong magnetic field
• The S=1/2 chain in a staggered field: High-energy bound-spinon state and the effects of a discrete lattice