Publication Date:
2016-06-14
Description:
We report a heat switch effect in single crystals of an antiferromagnet Co 3 V 2 O 8 , that is, the thermal conductivity ( κ ) can be changed with magnetic field in an extremely large scale. Due to successive magnetic phase transitions at 12–6 K, the zero-field κ ( T ) displays a deep minimum at 6.7 K and rather small magnitude at low temperatures. Both the temperature and field dependencies of κ demonstrate that the phonons are strongly scattered at the regime of magnetic phase transitions. Magnetic field can suppress magnetic scattering effect and significantly recover the phonon thermal conductivity. In particular, a 14 T field along the a axis increases the κ at 7.5 K up to 100 times. For H ∥ c , the magnitude of κ can be suppressed down to ∼8% at some field-induced transition and can be enhanced up to 20 times at 14 T. The present results demonstrate that it is possible to design a kind of heat switch in the family of magnetic materials.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
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