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arXiv · 2202.08989

Enhanced two-component superconductivity in CoSi2/TiSi2 heterojunctions

Shao-Pin Chiu·Vivek Mishra·Yu Li·Fu-Chun Zhang·Stefan Kirchner·Juhn-Jong Lin
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Abstract

We report enhanced two-component superconductivity in (CoSi2/Si)/TiSi2 superconductor/normal-metal (S/N) heterojunctions. An enhanced superconducting transition temperature about twice that of CoSi2 and an upper critical field about 20 times bigger than that of epitaxial CoSi2/Si films were found. The tunneling spectra of three-terminal S/N junctions show pronounced zero-bias conductance peaks (ZBCPs) that signify penetration of odd-frequency, spin-triplet and even-parity Cooper pairs in TiSi2 from triplet dominant pairing in CoSi2/Si driven by symmetry reduction at the CoSi2/Si interface. Both the enhancement of the superconducting transition temperature and the ZBCPs are found to be more pronounced if TiSi2 is made more diffusive.

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Shao-Pin Chiu, Vivek Mishra, Yu Li, Fu-Chun Zhang, Stefan Kirchner, Juhn-Jong Lin. 2022-02-18. Enhanced two-component superconductivity in CoSi2/TiSi2 heterojunctions. https://arxiv.org/abs/2202.08989

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