Collective Phenomea In Highly Excited Bose Gas
| dc.contributor.author | Tilahun, Tesfaye | |
| dc.date.accessioned | 2018-07-05T12:24:22Z | |
| dc.date.accessioned | 2023-11-09T11:24:26Z | |
| dc.date.available | 2018-07-05T12:24:22Z | |
| dc.date.available | 2023-11-09T11:24:26Z | |
| dc.date.issued | 1981-06 | |
| dc.description.abstract | e}wij:ed gas is meant a 90."1 in which thet'e exisi: a s.i9nificant number of exalted particles. Tlw number of ~jxcited part 1cles depends on external sources (la.ser illumination, electron beams, etc.) and can be arbitrary. In typical case" the number of excited atoms N .i" smaller than the number of pal;t.icles .in the 1 ground state. As.is \'1e11 lmoVin the energy of interaction between pa,'ticles in the same quantum Bt_ate is proportional to lid' ~Ihere R 1s the distance between partlcles. 'I'his shortrange interaction is responslblc 1:or tho coll()ct:i,ve properties of 1:he convelltional gas Huch as condensation and pha"e transitions. '1'he int_m:action hel:vl8cn dlf ferently·-exci'ced particles 1s proportional to I/n 3 and can be 21ttnlctive as Vlell as repulsive. 'rhus, t_he ava:llab.il.ity of even a comparaU.vely small number of excited -paxticles can and does l(-lad to 21 signU'icant change of the propertles of th,~ gas compared \~i til the non-(~xcited gas. The properties of Huch exc:l.tec1 (jas are invest.i.gated on the basis of the second'-quantJzecl Hilmil tonian and the method of equations of IUo-tion of Green functions. 1~hiB method yields I in a most natural and direct "THY, the enor(w~spectrulU of elllmentary excitations and t:he t:hGl:l!lodynaroiGCll functions of excited gas | en_US |
| dc.identifier.uri | http://10.90.10.223:4000/handle/123456789/6714 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Collective Phenomea | en_US |
| dc.title | Collective Phenomea In Highly Excited Bose Gas | en_US |
| dc.type | Thesis | en_US |