Photoemission studies in MgB2
نویسندگان
چکیده
Photoemission spectroscopy measurements of MgB2 are reviewed. From angle-resolved photoemission spectroscopy, band dispersion is observed as is theoretically predicted, suggesting that the electronic structure of MgB2 is well described within band theory. From angle-integrated photoemission spectroscopy, a clear peak ascribed to the superconducting coherent peak is observed. The shape of the spectral line shape is consistent with the presence of s-wave gap(s). The estimated size of superconducting gap is close to the conventional BCS prediction, supporting the idea that this material is an electron–phonon mediated superconductor. At the same time, the presence of second gap with a smaller size is indicated by the high-resolution photoemission spectroscopy. 2002 Elsevier Science B.V. All rights reserved. PACS: 74.70.Ad; 74.25.Jb; 79.60.Bm
منابع مشابه
High-resolution photoemission study of MgB2.
We have performed high-resolution photoemission spectroscopy on MgB2 and observed opening of a superconducting gap with a narrow coherent peak. We found that the superconducting gap is s like with the gap value ( Delta) of 4.5+/-0.3 meV at 15 K. The temperature dependence (15-40 K) of the gap value follows well the BCS form, suggesting that 2Delta/k(B)T(c) at T = 0 is about 3. No pseudogap beha...
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