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Macroscopic evidence for quantum criticality and field-induced quantum fluctuations in cuprate superconductors

A. D. Beyer·V. S. Zapf·H. Yang·F. Fabris·M. S. Park·K. H. Kim·S. -I. Lee·N. -C. Yeh
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Abstract

We present macroscopic experimental evidence for field-induced microscopic quantum fluctuations in different hole- and electron-type cuprate superconductors with varying doping levels and numbers of CuO$_2$ layers per unit cell. The significant suppression of the zero-temperature in-plane magnetic irreversibility field relative to the paramagnetic field in all cuprate superconductors suggests strong quantum fluctuations due to the proximity of the cuprates to quantum criticality.

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A. D. Beyer, V. S. Zapf, H. Yang, F. Fabris, M. S. Park, K. H. Kim, S. -I. Lee, N. -C. Yeh. 2007-10-09. Macroscopic evidence for quantum criticality and field-induced quantum fluctuations in cuprate superconductors. https://doi.org/10.1103/physrevb.76.140506

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