Anisotropic superconductivity in NbSe2 probed by magnetic penetration depth

✍ Scribed by P. Diener; P. Rodière; J.D. Fletcher; A. Carrington; J.P. Brison; R. Prozorov; T. Olheiser; R.W. Giannetta

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 142 KB
• Volume: 460-462
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2007.03.145

✦ Synopsis

NbSe 2 shows coexistence of a charge density wave (T CDW $ 32 K) with a superconducting state below T = 7.2 K. Recent ARPES measurements revealed different values of the superconducting gap on the main sheets of the Fermi surface. These results suggest a multigap superconductivity such as in MgB 2 . The temperature dependence of the magnetic penetration depth (k(T)) down to T c /16 has been measured on high quality single crystals in the Meissner state. A strong increase of the in-plane penetration depth is observed, signaling the presence of low lying excitations. Given the relative contributions of each Fermi surface sheet, these measurements indicate that a reduced gap is not necessarily only found on the small Se sheet as suggested by the ARPES measurements. These results are discussed in a framework of multigap superconductivity.