AC susceptibility study of superconducting aluminium-doped silicon carbide

M. Kriener; T. Muranaka; J. Akimitsu; Y. Maeno

doi:10.1016/j.physc.2009.12.009

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arXiv · 0908.0622

AC susceptibility study of superconducting aluminium-doped silicon carbide

M. Kriener·T. Muranaka·J. Akimitsu·Y. Maeno

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Abstract

In 2007, type-I superconductivity in heavily boron-doped silicon carbide was discovered. The question arose, if it is possible to achieve a superconducting phase by introducing dopants different from boron. Recently, aluminum-doped silicon carbide was successfully found to superconduct by means of resistivity and DC magnetization measurements. In contrast to boron-doped silicon carbide, the aluminum doped system is treated as a type-II superconductor because of the absence of an hysteresis in data measured upon decreasing and increasing temperature in finite magnetic fields. In this paper, results of a recent AC susceptibility study on aluminum-doped silicon carbide are presented. In higher applied DC magnetic fields and at low temperatures, a weak indication of supercooling with a width of a few mK is found. This supports the conclusion that aluminum-doped silicon carbide is located near to the border between type-I and type-II superconductivity, as pointed out in a recent theoretical work, too.

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M. Kriener, T. Muranaka, J. Akimitsu, Y. Maeno. 2009-08-05. AC susceptibility study of superconducting aluminium-doped silicon carbide. https://doi.org/10.1016/j.physc.2009.12.009

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