1306.3042 (J. A. Galvis et al.)

Scanning Tunneling Microscopy in the superconductor LaSb2    [PDF]

J. A. Galvis, H. Suderow, S. Vieira, S. L. Bud'ko, P. C. Canfield

We present very low temperature (0.15 K) scanning tunneling microscopy and spectroscopy experiments in the layered superconductor LaSb$_2$. We obtain topographic microscopy images with surfaces showing hexagonal and square atomic size patterns, and observe in the tunneling conductance a superconducting gap. We find well defined quasiparticle peaks located at a bias voltage comparable to the weak coupling s-wave BCS expected gap value (0.17 meV). The amount of states at the Fermi level is however large and the curves are significantly broadened. We find T$_c$ of 1.2 K by following the tunneling conductance with temperature.

View original: http://arxiv.org/abs/1306.3042