Observation of Andreev bound state and multiple energy gaps in the non-centrosymmetric superconductor BiPd

Mintu Mondal; Bhanu Joshi; Sanjeev Kumar; Anand Kamlapure; Somesh Chandra Ganguli; Arumugam Thamizhavel; Sudhansu S Mandal; Srinivasan Ramakrishnan; Pratap Raychaudhuri

doi:10.1103/physrevb.86.094520

arXiv · 1202.2454

Observation of Andreev bound state and multiple energy gaps in the non-centrosymmetric superconductor BiPd

Mintu Mondal·Bhanu Joshi·Sanjeev Kumar·Anand Kamlapure·Somesh Chandra Ganguli·Arumugam Thamizhavel·Sudhansu S Mandal·Srinivasan Ramakrishnan·Pratap Raychaudhuri

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Abstract

We report directional point contact Andreev reflection (PCAR) measurements on high-quality single crystals of the non-centrosymmetric superconductor, BiPd. The PCAR spectra measured on different crystallographic faces of the single crystal clearly show the presence of multiple superconducting energy gaps. For point contacts with low resistance, in addition to the superconducting gap feature, a pronounced zero bias conductance peak is observed. These observations provide strong evidence of the presence of unconventional order parameter in this material.

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Mintu Mondal, Bhanu Joshi, Sanjeev Kumar, Anand Kamlapure, Somesh Chandra Ganguli, Arumugam Thamizhavel, Sudhansu S Mandal, Srinivasan Ramakrishnan, Pratap Raychaudhuri. 2012-02-11. Observation of Andreev bound state and multiple energy gaps in the non-centrosymmetric superconductor BiPd. https://doi.org/10.1103/physrevb.86.094520

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