- LandOfFree
- Scientists
- Physics
- Condensed Matter
- Strongly Correlated Electrons
Details
Two Superconducting Phases in the d=3 Hubbard Model: Phase Diagram and
Specific Heat from Renormalization-Group Calculations
Two Superconducting Phases in the d=3 Hubbard Model: Phase Diagram and
Specific Heat from Renormalization-Group Calculations
2005-03-09
-
arxiv.org/abs/cond-mat/0503226v2
Eur. Phys. J. B 48, 1 (2005)
Physics
Condensed Matter
Strongly Correlated Electrons
16 pages, 10 figures; typos in Fig. 2 corrected
Scientific paper
10.1140/epjb/e2005-00376-y
The phase diagram of the d=3 Hubbard model is calculated as a function of temperature and electron density n_i, in the full range of densities between 0 and 2 electrons per site, using renormalization-group theory. An antiferromagnetic phase occurs at lower temperatures, at and near the half-filling density of = 1. The antiferromagnetic phase is unstable to hole or electron doping of at most 15%, yielding to two distinct "tau" phases: for large coupling U/t, one such phase occurs between 30-35% hole or electron doping, and for small to intermediate coupling U/t another such phase occurs between 10-18% doping. Both tau phases are distinguished by non-zero hole or electron hopping expectation values at all length scales. Under further doping, the tau phases yield to hole- or electron-rich disordered phases. We have calculated the specific heat over the entire phase diagram. The low-temperature specific heat of the weak-coupling tau phase shows a BCS-type exponential decay, indicating a gap in the excitation spectrum, and a cusp singularity at the phase boundary. The strong-coupling tau phase, on the other hand, has characteristics of BEC-type superconductivity, including a critical exponent alpha approximately equal to -1, and an additional peak in the specific heat above the transition temperature indicating pair formation. In the limit of large Coulomb repulsion, the phase diagram of the tJ model is recovered.
Affiliated with
Also associated with
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
Two Superconducting Phases in the d=3 Hubbard Model: Phase Diagram and
Specific Heat from Renormalization-Group Calculations 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 Two Superconducting Phases in the d=3 Hubbard Model: Phase Diagram and
Specific Heat from Renormalization-Group Calculations, we encourage you to share that experience with our LandOfFree.com community.
Your opinion is very important and Two Superconducting Phases in the d=3 Hubbard Model: Phase Diagram and
Specific Heat from Renormalization-Group Calculations will most certainly appreciate the feedback.
Rate now
Profile ID: LFWR-SCP-O-369450
All data on this website is collected from public sources.
Our data reflects the most accurate information available at the time of publication.