Magnetic and Metal-Insulator Transitions through Bandwidth Control in Two-Dimensional Hubbard Models with Nearest and Next-Nearest Neighbor Transfers
| dc.creator | Kashima, Tsuyoshi | |
| dc.creator | Imada, Masatoshi | |
| dc.date | 2001-04-19 | |
| dc.date | 2001-08-10 | |
| dc.date.accessioned | 2026-07-07T02:41:07Z | |
| dc.date.available | 2026-07-07T02:41:07Z | |
| dc.description | Numerical studies on Mott transitions caused by the control of the ratio between bandwidth and electron-electron interaction ($U$) are reported. By using the recently proposed path-integral renormalization group(PIRG) algorithm, physical properties near the transitions in the ground state of two-dimensional half-filled models with the nearest and the next-nearest neighbor transfers ($-t$ and $t'$, respectively) are studied as a prototype of geometrically frustrated system. The nature of the bandwidth-control transitions shows sharp contrast with that of the filling-control transitions: First, the metal-insulator and magnetic transitions are separated each other and the metal-insulator (MI) transition occurs at smaller $U$, although the both transition interactions $U$ increase with increasing $t'$. Both transitions do not contradict the first-order transitions for smaller $t'/t$ while the MI transitions become continuous type accompanied by emergence of {\it unusual metallic phase} near the transition for large $t'/t$. A nonmagnetic insulator phase is stabilized between MI and AF transitions. The region of the nonmagnetic insulator becomes wider with increasing $t'/t$. The phase diagram naturally connects two qualitatively different limits, namely the Hartree-Fock results at small $t'/t$ and speculations in the strong coupling Heisenberg limit. | |
| dc.description | 30 pages including 20 figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0104348 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0104348 | |
| dc.identifier | J. Phys. Soc. Jpn. 70 (2001) 3052 | |
| dc.identifier | doi:10.1143/JPSJ.70.3052 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/17624 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.title | Magnetic and Metal-Insulator Transitions through Bandwidth Control in Two-Dimensional Hubbard Models with Nearest and Next-Nearest Neighbor Transfers | |
| dc.type | text |