Crossover of spectral features from Dimerized to Haldane behavior in alternating antiferromagnetic-ferromagnetic spin-half chains
| dc.creator | Zheng, Weihong | |
| dc.creator | Hamer, Chris | |
| dc.creator | Singh, Rajiv | |
| dc.date | 2006-05-15 | |
| dc.date.accessioned | 2026-07-07T07:08:56Z | |
| dc.date.available | 2026-07-07T07:08:56Z | |
| dc.description | We calculate the excitation spectrum and spectral weights of the alternating antiferromagnetic-ferromagnetic spin-half Heisenberg chain with exchange couplings $J$ and $-|λ|J$ as a power series in $λ$. For small $|λ|$, the gapped one-particle spectrum has a maximum at $k=0$ and there is a rich structure of bound (and anti-bound) states below (and above) the 2-particle continuum. As $|λ|$ is increased past unity the spectrum crosses over to the Haldane regime, where the peak shifts away from $k=0$, the one particle states merge with the bottom of the continuum near $k=0$, and the spectral weights associated with the one-particle states become very small. Extrapolation of the spectrum to large $|λ|$ confirms that the ground state energy and excitation gap map onto those of the spin-one chain. | |
| dc.description | 4 pages, 8 figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0605370 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0605370 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/110892 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.subject | Statistical Mechanics | |
| dc.title | Crossover of spectral features from Dimerized to Haldane behavior in alternating antiferromagnetic-ferromagnetic spin-half chains | |
| dc.type | text |