For the first time, we experimentally discovered a new quantum phase transition, i.e. quantum Griffiths singularity, in two-dimensional superconducting thin films, which reveals the prominent influence of disorder and dissipation on quantum phase transitions and expands the universality class of quantum phase transitions. Over the past decade, this discovery has become a universal phenomenon across various two-and three-dimensional superconducting systems, and evolved into a paradigm for studying disorder-induced quantum phase transitions for both conventional and unconventional superconductors.

References

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