Erick Andrade

Scanning Tunneling Spectroscopy Probing the Origin of Charge
Density Waves in NbSe2
Erick F. Andrade1, C.J.Arguello1, E.Rosenthal1, W. Jin1, P. C. Yeh1, N. Zaki1, R. M. Fernandes2, A.J.Millis1,
R. M. Osgood1, A. N. Pasupathy1
Columbia University, 2University of Minnesota
Using scanning tunneling microscopy, we address the relationship between
quasiparticle interference, the charge susceptibility and the scattering potential in
2H-NbSe2. We show that the charge susceptibility in a quasi-2D material can be
directly obtained from quasiparticle interference images, and with the additional
ARPES bandstructure measurements, one can extract the wavevector
dependence of the scattering potential. Applying these concepts to lightly sulfurdoped 2H-NbSe2, we show that Fermi surface nesting is inconsequential to the
charge density wave formation in this material, and that interband scattering
dominates possibly arising from strong electron-phonon coupling.