STM evidence of room-temperature charge instabilities in NbSe3.

Magnetic-field effects in NbSe3.

We have performed NMR studies on an aligned, multicrystalline NbSe3 sample at various temperatures. We find conclusive evidence of field-induced Fermi-surface changes at low temperatures, and associate these changes with charge-density-wave (CDW) enhancement mainly localized on the yellow crystallographic site, contrary to expectations, since the low-temperature CDW is mainly localized on the o...

Unusual spectral behavior of charge-density waves with imperfect nesting in a quasi-one-dimensional metal.

Low-temperature electronic properties of the charge-density-wave system NbSe3 are reported from angle-resolved photoemission at 15 K. The effect of two instabilities q(1) and q(2) on the k-resolved spectral function is observed for the first time. With a pseudogap background, the gap spectra exhibit maxima at Delta*(1) approximately 110 meV and Delta*(2) approximately 45 meV. Imperfectly nested...

Optical investigation of the charge-density-wave phase transitions in NbSe3

We have measured the optical reflectivity R(v) of the quasi-one-dimensional conductor NbSe3 from the far infrared up to the ultraviolet between 10 and 300 K using light polarized along and normal to the chain axis. We find a depletion of the optical conductivity with decreasing temperature for both polarizations in the midto far-infrared region. This leads to a redistribution of spectral weight...

NMR relaxation studies of electronic structure in NbSe3.

NMR spin-lattice relaxation measurements of the 'Nb resonance for each Nb site were performed on an aligned, multicrystalline NbSe3 sample at different temperatures. Results are associated with local electron densities of states for each of the three crystallographic sites, demonstrating Fermi-surface changes associated with the two charge-density-wave phase transitions. The most significant Fe...

Scanning tunneling microscopy at the NbSe3 surface: Evidence for interaction between q(1) and q(2) charge density waves in the pinned regime