A modified Bogoliubov method applied to a simple boson model
| Autor: | O. Litt, W. H. Bassichis |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Physics
Annihilation Born–Huang approximation Statistical and Nonlinear Physics 01 natural sciences 010305 fluids & plasmas symbols.namesake Operator (computer programming) Exact results Quantum mechanics 0103 physical sciences symbols 010306 general physics Hamiltonian (quantum mechanics) Ground state Mathematical Physics Eigenvalues and eigenvectors Boson Mathematical physics |
| Zdroj: | Theoretical and Mathematical Physics. 190:109-119 |
| ISSN: | 1573-9333 0040-5779 |
| DOI: | 10.1134/s0040577917010093 |
| Popis: | We use a non-gauge-invariant modification of the exact Hamiltonian to obtain a new Hamiltonian-like operator for a simple exactly solvable boson model. The eigenvalues of the new operator are close to those of the original Hamiltonian. We make a one-body approximation of the new two-body operator in the spirit of the Bogoliubov approximation. Because only the number operator appears, the c-number approximation is not required individually for the creation or annihilation operators in the ground state. For the simple model, the results using the new approximation are closer to the exact results than the usual Bogoliubov results over a wide range of parameters. The improvement increases dramatically as the model interaction strength increases. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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