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Transverse voltage in zero external magnetic fields, its scaling and violation of the time reversal symmetry in MgB2

P. Vasek
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Abstract

The longitudinal and transverse voltages (resistances) have been measured for MgB$_2$ in zero external magnetic fields. Samples were prepared in the form of thin film and patterned into the usual Hall bar shape. In close vicinity of the critical temperature T$_c$ non-zero transverse resistance has been observed. Its dependence on the transport current has been also studied. New scaling between transverse and longitudinal resistivities has been observed in the form $ρ{_{xy}}\sim dρ{_{xx}}/dT$. Several models for explanation of the observed transverse resistances and breaking of reciprocity theorem are discussed. One of the most promising explanation is based on the idea of time-reversal symmetry violation.

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P. Vasek. 2003-10-07. Transverse voltage in zero external magnetic fields, its scaling and violation of the time reversal symmetry in MgB2. https://doi.org/10.1016/j.physc.2004.07.011

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