Little-Parks oscillations with half-quantum fluxoid features in Sr2RuO4 microrings

Article

关键词: SPIN-TRIPLET SUPERCONDUCTIVITY;    MAJORANA FERMIONS;    TEMPERATURE;    BREAKING;   

DOI  :  10.1103/PhysRevB.96.180507

来源: SCIE

【 摘 要 】

In a microring of a superconductor with a spin-triplet equal-spin pairing state, a fluxoid, a combined object of magnetic flux and circulating supercurrent, can penetrate as half-integer multiples of the flux quantum. A candidate material to investigate such half-quantum fluxoids is Sr2RuO4. We fabricated Sr2RuO4 microrings using single crystals and measured their resistance behavior under magnetic fields controlled with a three-axis vector magnet. Proper Little-Parks oscillations in the magnetovoltage as a function of an axially applied field, associated with fluxoid quantization, are clearly observed using bulk single-crystalline superconductors. We then performed magnetovoltage measurements with additional in-plane magnetic fields. By carefully analyzing both the voltages V+ (V-) measured at positive (negative) current, we find that, above an in-plane threshold field of about 10 mT, the magnetovoltage maxima convert to minima. We interpret this behavior as the peak splitting expected for the half-quantum fluxoid states.

【 授权许可】

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