Microwave Spectroscopy of PrOs_4Sb_12: Josephson-Coupled Two-Band Superconductivity and Itinerant f Electrons

D. M. Broun; P. J. Turner; G. K. Mullins; D. E. Sheehy; X. G. Zheng; S. K. Kim; N. A. Frederick; M. B. Maple; W. N. Hardy; D. A. Bonn

arXiv · cond-mat/0310613

Microwave Spectroscopy of PrOs_4Sb_12: Josephson-Coupled Two-Band Superconductivity and Itinerant f Electrons

D. M. Broun·P. J. Turner·G. K. Mullins·D. E. Sheehy·X. G. Zheng·S. K. Kim·N. A. Frederick·M. B. Maple·W. N. Hardy·D. A. Bonn

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Abstract

We report microwave surface impedance measurements made on a single crystal of PrOs_4Sb_12 across the frequency range 0.5 to 21 GHz. The penetration depth data provide clear thermodynamic evidence for superconductivity arising in two bands coupled by Josephson pair-tunneling, indicating two order parameters with the same symmetry. Detailed conductivity spectra obtained using high-resolution bolometry confirm this picture and extend it, revealing the itinerant nature of the Pr f electrons through the observation of quasiparticles with heavily renormalized mass.

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D. M. Broun, P. J. Turner, G. K. Mullins, D. E. Sheehy, X. G. Zheng, S. K. Kim, N. A. Frederick, M. B. Maple, W. N. Hardy, D. A. Bonn. 2003-10-26. Microwave Spectroscopy of PrOs_4Sb_12: Josephson-Coupled Two-Band Superconductivity and Itinerant f Electrons. https://arxiv.org/abs/cond-mat/0310613

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