Dynamical behavior across the Mott transition of two bands with different bandwidths

Physics – Condensed Matter – Strongly Correlated Electrons

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

11 pages, 12 figures

Scientific paper

10.1103/PhysRevB.72.205126

We investigate the role of the bandwidth difference in the Mott metal-insulator transition of a two-band Hubbard model in the limit of infinite dimensions, by means of a Gutzwiller variational wave function as well as by dynamical mean-field theory. The variational calculation predicts a two-stage quenching of the charge degrees of freedom, in which the narrower band undergoes a Mott transition before the wider one, both in the presence and in the absence of a Hund's exchange coupling. However, this scenario is not fully confirmed by the dynamical mean-field theory calculation, which shows that, although the quasiparticle residue of the narrower band is zero within our numerical accuracy, low-energy spectral weight still exists inside the Mott-Hubbard gap, concentrated into two peaks symmetric around the chemical potential. This spectral weight vanishes only when the wider band ceases to conduct too. Although our results are compatible with several scenarios, e.g., a narrow gap semiconductor or a semimetal, we argue that the most plausible one is that the two peaks coexist with a narrow resonance tied at the chemical potential, with a spectral weight below our numerical accuracy. This quasiparticle resonance is expected to vanish when the wider band undergoes the Mott transition.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Dynamical behavior across the Mott transition of two bands with different bandwidths does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Dynamical behavior across the Mott transition of two bands with different bandwidths, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamical behavior across the Mott transition of two bands with different bandwidths will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-720933

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.