Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2004-06-27
J. Phys.: Condens. Matter 16 (2004) 7063-7081
Physics
Condensed Matter
Strongly Correlated Electrons
21 pages, 7 figures, submitted to Journal of Physics: Condensed Matter
Scientific paper
10.1088/0953-8984/16/39/038
We study the Hubbard model at half band-filling on a Bethe lattice with infinite coordination number in the paramagnetic insulating phase at zero temperature. We use the dynamical mean-field theory (DMFT) mapping to a single-impurity Anderson model with a bath whose properties have to be determined self-consistently. For a controlled and systematic implementation of the self-consistency scheme we use the fixed-energy (FE) approach to the DMFT. In FE-DMFT the onset and the width of the Hubbard bands are adjusted self-consistently but the energies of the bath levels are kept fixed relatively to both band edges during the calculation of self-consistent hybridization strengths between impurity and bath sites. Using the dynamical density-matrix renormalization group method (DDMRG) we calculate the density of states with a resolution ranging from 3% of the bare bandwidth $W=4t$ at high energies to 0.5% in the vicinity of the gap. The DDMRG resolution and accuracy for the density of states and the gap is superior to those obtained with other numerical methods in previous DMFT investigations. We find that the Mott gap closes at a critical coupling $U_{\rm c}/t=4.45 \pm 0.05$. At $U=4.5t$, we observe prominent shoulders near the onset of the Hubbard bands. They are the remainders of the quasi-particle resonance in the metallic phase which appears to split when the gap opens at $U_{\rm c}$.
Gebhard Florian
Jeckelmann Eric
Nishimoto Satoshi
No associations
LandOfFree
Dynamical Density-Matrix Renormalization Group for the Mott--Hubbard insulator in high dimensions 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 Density-Matrix Renormalization Group for the Mott--Hubbard insulator in high dimensions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamical Density-Matrix Renormalization Group for the Mott--Hubbard insulator in high dimensions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-281034