Magnetic-Field Induced Gap in One-Dimensional Antiferromagnet KCuGaF6
نویسندگان
چکیده
Magnetic susceptibility and specific heat measurements in magnetic fields were performed on an S = 1/2 one-dimensional antiferromagnet KCuGaF6. Exchange interaction was evaluated as J/kB ≃ 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.
منابع مشابه
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