Continuous unitary transformations in two-level boson systems
Two-level boson systems displaying a quantum phase transition from a spherical (symmetric) to a deformed (broken) phase are studied. A formalism to diagonalize Hamiltonians with O(2L + 1) symmetry for large number of bosons is worked out. Analytical results beyond the simple mean-field treatment are...
| Authors: | ; ; ; ; |
|---|---|
| Format: | Article |
| Publication date: | 2005 |
| Country: | España |
| Institution: | Universidad de Huelva (UHU) |
| Repository: | Arias Montano. Repositorio Institucional de la Universidad de Huelva |
| Language: | English |
| OAI Identifier: | oai:ariasmontano.uhu.es:10272/5500 |
| Online Access: | http://hdl.handle.net/10272/5500 |
| Access Level: | Open access |
| Keyword: | Quantum phase transitions Interacting Boson Model |
| Summary: | Two-level boson systems displaying a quantum phase transition from a spherical (symmetric) to a deformed (broken) phase are studied. A formalism to diagonalize Hamiltonians with O(2L + 1) symmetry for large number of bosons is worked out. Analytical results beyond the simple mean-field treatment are deduced by using the continuous unitary transformations technique. In this scheme, a 1/N expansion for different observables is proposed and allows one to compute the finite-size scaling exponents at the critical point. Analytical and numerical results are compared and reveal the power of the present approach to compute the finite-size corrections in such a context. |
|---|