Quantitative analysis of quantum phase slips in superconducting Mo76Ge24 nanowires revealed by switching-current statistics

  title={Quantitative analysis of quantum phase slips in superconducting Mo76Ge24 nanowires revealed by switching-current statistics},
  author={Thomas Aref and Alexander Alexeevich Levchenko and Victor Vakaryuk and Alexey Bezryadin},
  journal={Physical Review B},
We measure quantum and thermal phase-slip rates using the standard deviation of the switching current in superconducting nanowires at high bias current. Our rigorous quantitative analysis provides firm evidence for the presence of quantum phase slips (QPS) in homogeneous nanowires. We observe that as temperature is lowered, thermal fluctuations freeze at a characteristic crossover temperature Tq, below which the dispersion of the switching current saturates to a constant value, indicating the… 

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