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Electronic structure of single-crystalline Mg(x)Al(1-x)B(2)

S. Schuppler·E. Pellegrin·N. Nuecker·T. Mizokawa·M. Merz·D. A. Arena·J. Dvorak·Y. U. Idzerda·D. -J. Huang·C. -F. Cheng·K. -P. Bohnen·R. Heid·P. Schweiss·Th. Wolf
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Abstract

Polarization-dependent x-ray absorption spectroscopy at the B 1s edge of single-crystalline Mg(x)Al(1-x)B(2) reveals a strongly anisotropic electronic structure near the Fermi energy. Comparing spectra for superconducting compounds (x=0.9, 1.0) with those for the non-superconductor x=0.0 gives direct evidence on the importance of an in-plane spectral feature crossing E_F for the superconducting properties of the diborides. Good agreement is found with the projected B 2p density of states from LDA band structure calculations.

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S. Schuppler, E. Pellegrin, N. Nuecker, T. Mizokawa, M. Merz, D. A. Arena, J. Dvorak, Y. U. Idzerda, D. -J. Huang, C. -F. Cheng, K. -P. Bohnen, R. Heid, P. Schweiss, Th. Wolf. 2002-05-10. Electronic structure of single-crystalline Mg(x)Al(1-x)B(2). https://arxiv.org/abs/cond-mat/0205230

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