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New High Temperature Diboride Superconductors: AgB2 and AuB2

S. K. Kwon·S. J. Youn·K. S. Kim·B. I. Min
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Abstract

Based on electronic structure calculations, we have found that noble metal diborides, AgB2 and AuB2, are potential candidates for conventional BCS-type high temperature superconductors. B 2p density of states dominates at the Fermi level in comparison with Ag 4d and Au 5d states. Furthermore, the electron-phonon coupling constant λis much larger in AgB2 and AuB2 than in MgB2. Estimated transition temperatures for AgB2 and AuB2 are T_c = 59 K and 72 K, respectively. These are about 2 ~ 3 times higher than the estimated T_c = 27 K in MgB2 and almost comparable to those in cuprate superconductors.

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S. K. Kwon, S. J. Youn, K. S. Kim, B. I. Min. 2001-06-23. New High Temperature Diboride Superconductors: AgB2 and AuB2. https://arxiv.org/abs/cond-mat/0106483

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