Excitation spectrum and structure factor of a two-component Bose-Einstein condensate in different hyperfine states
The elementary excitation spectrum of a two-component Bose-Einstein condensate in different hyperfine states is obtained by Green's function method. It is found to have two branches. In the long wave-length limit, the two branches of the excitation spectrum are reduced to one phonon excitation and o...
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| Published in | Chinese physics B Vol. 22; no. 8; pp. 290 - 297 |
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| Main Author | |
| Format | Journal Article |
| Language | English |
| Published |
01.08.2013
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| Subjects | |
| Online Access | Get full text |
| ISSN | 1674-1056 2058-3834 1741-4199 |
| DOI | 10.1088/1674-1056/22/8/080308 |
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| Summary: | The elementary excitation spectrum of a two-component Bose-Einstein condensate in different hyperfine states is obtained by Green's function method. It is found to have two branches. In the long wave-length limit, the two branches of the excitation spectrum are reduced to one phonon excitation and one single-particle excitation. The single-particle one has an energy gap. When the energy gap exists, we study the Landau critical velocity and the depletion of the condensate. With the obtained Green's functions, we calculate the structure factor of a two-component condensate. It is found that the static structure factor comprises only the branch of the phonon excitation and the single-particle excitation makes no contribution to the structure factor. |
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| Bibliography: | elementary excitation, Bose-Einstein condensate, structure factor Han Yu-Feng, Chen Liang, Liu Hou-Tong, and Huang Xian-Shan Department of Mathematics and Physics, Anhui University of Technology, Ma' anshan 243032, China b) Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China The elementary excitation spectrum of a two-component Bose-Einstein condensate in different hyperfine states is obtained by Green's function method. It is found to have two branches. In the long wave-length limit, the two branches of the excitation spectrum are reduced to one phonon excitation and one single-particle excitation. The single-particle one has an energy gap. When the energy gap exists, we study the Landau critical velocity and the depletion of the condensate. With the obtained Green's functions, we calculate the structure factor of a two-component condensate. It is found that the static structure factor comprises only the branch of the phonon excitation and the single-particle excitation makes no contribution to the structure factor. 11-5639/O4 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
| ISSN: | 1674-1056 2058-3834 1741-4199 |
| DOI: | 10.1088/1674-1056/22/8/080308 |