Scanning tunneling microscopy/spectroscopy of vortices in LiFeAs

Multiquantum vortices in superconductors: Electronic and scanning tunneling microscopy spectra

Superconducting quasiparticle excitation spectra are computed for m times quantized flux lines using a self-consistent Bogoliubov–de Gennes approach. We find m discrete branches of bound-state solutions in the spectrum, corresponding to different values of the quasiparticle angular momentum. Owing to the bound states, the scanning tunneling microscopy spectrum of the vortex is predicted to disp...

Scanning tunneling spectroscopy of superconducting LiFeAs single crystals: evidence for two nodeless energy gaps and coupling to a bosonic mode.

The superconducting compound LiFeAs is studied by scanning tunneling microscopy and spectroscopy. A gap map of the unreconstructed surface indicates a high degree of homogeneity in this system. Spectra at 2 K show two nodeless superconducting gaps with Δ(1)=5.3±0.1 meV and Δ(2)=2.5±0.2 meV. The gaps close as the temperature is increased to the bulk T(c), indicating that the surface accurately r...

Microscopy, Scanning Tunneling

Ultrafast Scanning Tunneling Microscopy

Scanning Tunneling Microscopy

The invention of the scanning tunneling microscope was a singularity event in the field of surface science and condensed matter physics. The ability to visualize individual atoms in an atomic structure was a huge step forward in experimental development, one for which the inventors were awarded the Nobel Prize in Physics in 1986. While a groundbreaking development, the Scanning Tunneling Micros...