0000000001307016
AUTHOR
E. Navarro-moratalla
Zero-bias conductance peak in detached flakes of superconducting 2H-TaS$_2$ probed by scanning tunneling spectroscopy
We report an anomalous tunneling conductance with a zero bias peak in flakes of superconducting 2H-TaS$_2$ detached through mechanical exfoliation. To explain the observed phenomenon, we construct a minimal model for a single unit cell layer of superconducting 2H-TaS$_2$ with a simplified 2D Fermi surface and sign-changing Cooper pair wavefunction induced by Coulomb repulsion. Superconductivity is induced in the central $\Gamma$ pocket, where it becomes nodal. We show that weak scattering at the nodal Fermi surface, produced by non-perturbative coupling between tip and sample, gives Andreev states that lead to a zero bias peak in the tunneling conductance. We suggest that reducing dimension…
Scanning tunneling spectroscopy of layers of superconducting 2H-TaSe$_\textbf{2}$: Evidence for a zero bias anomaly in single layers
We report a characterization of surfaces of the dichalcogenide TaSe$_2$ using scanning tunneling microscopy and spectroscopy (STM/S) at 150 mK. When the top layer has the 2H structure and the layer immediately below the 1T structure, we find a singular spatial dependence of the tunneling conductance below 1 K, changing from a zero bias peak on top of Se atoms to a gap in between Se atoms. The zero bias peak is additionally modulated by the commensurate $3a_0 \times 3a_0$ charge density wave of 2H-TaSe$_2$. Multilayers of 2H-TaSe$_2$ show a spatially homogeneous superconducting gap with a critical temperature also of 1 K. We discuss possible origins for the peculiar tunneling conductance in …
Zero-bias conductance peak in detached flakes of superconducting 2 H - TaS2 probed by scanning tunneling spectroscopy
We report an anomalous tunneling conductance with a zero-bias peak in flakes of superconducting 2H-TaS2 detached through mechanical exfoliation. To explain the observed phenomenon, we construct a minimal model for a single unit cell layer of superconducting 2H-TaS2 with a simplified two-dimensional Fermi surface and a sign-changing Cooper-pair wave function induced by Coulomb repulsion. Superconductivity is induced in the central Γ pocket, where it becomes nodal. We show that weak scattering at the nodal Fermi surface, produced by nonperturbative coupling between tip and sample, gives Andreev states that lead to a zero-bias peak in the tunneling conductance. We suggest that reducing dimensi…
CCDC 915316: Experimental Crystal Structure Determination
Related Article: S. Cardona-Serra, J. M. Clemente-Juan, E. Coronado, C. Marti-Gastaldo, E. Navarro-Moratalla|2013|Eur.J.Inorg.Chem.||1903|doi:10.1002/ejic.201201390
CCDC 915317: Experimental Crystal Structure Determination
Related Article: S. Cardona-Serra, J. M. Clemente-Juan, E. Coronado, C. Marti-Gastaldo, E. Navarro-Moratalla|2013|Eur.J.Inorg.Chem.||1903|doi:10.1002/ejic.201201390