Spin correlation and superfluidity of trapped fermi atoms on an optical lattice

Masahiko Machida, Susumu Yamada, Yoji Ohashi, Hideki Matsumoto

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

We investigate a possibility of superfluidity in a trapped gas of Fermi atoms with repulsive interaction U in the presence of an optical lattice. Applying the exact diagonalization method to a one-dimensional fermion-Hubbard model including the trap potential, we find that, when U exceeds a critical value, the binding energy of two Fermi atoms becomes negative indicating that an attractive interaction effectively works. In this case, a "Mott core" appears in the trap center, where each site is occupied by one atom, and a large Cooper-pair amplitude develops between atoms in the left and right hand sides of this core. In order to clarify the origin of the attractive force, we compute a pseudo spin correlation between neighboring sites given by 〈SiSi+1〉. As a result, we find that a creation of a singlet pair between both sides of the Mott core is strongly coupled with a pseudo-spin singlet re-formation leading to an energy gain process.

Original languageEnglish
Title of host publicationAIP Conference Proceedings
Pages61-62
Number of pages2
Volume850
DOIs
Publication statusPublished - 2006
Externally publishedYes
EventLOW TEMPERATURE PHYSICS: 24th International Conference on Low Temperature Physics - LT24 - Orlando, FL, United States
Duration: 2006 Aug 102006 Oct 17

Other

OtherLOW TEMPERATURE PHYSICS: 24th International Conference on Low Temperature Physics - LT24
CountryUnited States
CityOrlando, FL
Period06/8/1006/10/17

Fingerprint

superfluidity
atoms
traps
binding energy
fermions
interactions
gases
energy

Keywords

  • Atomic fermi gas
  • Cooper pair
  • Exact diagonalization
  • Hubbard model
  • Mott insulator
  • Optical lattice

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Machida, M., Yamada, S., Ohashi, Y., & Matsumoto, H. (2006). Spin correlation and superfluidity of trapped fermi atoms on an optical lattice. In AIP Conference Proceedings (Vol. 850, pp. 61-62) https://doi.org/10.1063/1.2354607

Spin correlation and superfluidity of trapped fermi atoms on an optical lattice. / Machida, Masahiko; Yamada, Susumu; Ohashi, Yoji; Matsumoto, Hideki.

AIP Conference Proceedings. Vol. 850 2006. p. 61-62.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Machida, M, Yamada, S, Ohashi, Y & Matsumoto, H 2006, Spin correlation and superfluidity of trapped fermi atoms on an optical lattice. in AIP Conference Proceedings. vol. 850, pp. 61-62, LOW TEMPERATURE PHYSICS: 24th International Conference on Low Temperature Physics - LT24, Orlando, FL, United States, 06/8/10. https://doi.org/10.1063/1.2354607
Machida M, Yamada S, Ohashi Y, Matsumoto H. Spin correlation and superfluidity of trapped fermi atoms on an optical lattice. In AIP Conference Proceedings. Vol. 850. 2006. p. 61-62 https://doi.org/10.1063/1.2354607
Machida, Masahiko ; Yamada, Susumu ; Ohashi, Yoji ; Matsumoto, Hideki. / Spin correlation and superfluidity of trapped fermi atoms on an optical lattice. AIP Conference Proceedings. Vol. 850 2006. pp. 61-62
@inproceedings{b4694ac8be4342f587866e2a00039ba5,
title = "Spin correlation and superfluidity of trapped fermi atoms on an optical lattice",
abstract = "We investigate a possibility of superfluidity in a trapped gas of Fermi atoms with repulsive interaction U in the presence of an optical lattice. Applying the exact diagonalization method to a one-dimensional fermion-Hubbard model including the trap potential, we find that, when U exceeds a critical value, the binding energy of two Fermi atoms becomes negative indicating that an attractive interaction effectively works. In this case, a {"}Mott core{"} appears in the trap center, where each site is occupied by one atom, and a large Cooper-pair amplitude develops between atoms in the left and right hand sides of this core. In order to clarify the origin of the attractive force, we compute a pseudo spin correlation between neighboring sites given by 〈SiSi+1〉. As a result, we find that a creation of a singlet pair between both sides of the Mott core is strongly coupled with a pseudo-spin singlet re-formation leading to an energy gain process.",
keywords = "Atomic fermi gas, Cooper pair, Exact diagonalization, Hubbard model, Mott insulator, Optical lattice",
author = "Masahiko Machida and Susumu Yamada and Yoji Ohashi and Hideki Matsumoto",
year = "2006",
doi = "10.1063/1.2354607",
language = "English",
isbn = "0735403473",
volume = "850",
pages = "61--62",
booktitle = "AIP Conference Proceedings",

}

TY - GEN

T1 - Spin correlation and superfluidity of trapped fermi atoms on an optical lattice

AU - Machida, Masahiko

AU - Yamada, Susumu

AU - Ohashi, Yoji

AU - Matsumoto, Hideki

PY - 2006

Y1 - 2006

N2 - We investigate a possibility of superfluidity in a trapped gas of Fermi atoms with repulsive interaction U in the presence of an optical lattice. Applying the exact diagonalization method to a one-dimensional fermion-Hubbard model including the trap potential, we find that, when U exceeds a critical value, the binding energy of two Fermi atoms becomes negative indicating that an attractive interaction effectively works. In this case, a "Mott core" appears in the trap center, where each site is occupied by one atom, and a large Cooper-pair amplitude develops between atoms in the left and right hand sides of this core. In order to clarify the origin of the attractive force, we compute a pseudo spin correlation between neighboring sites given by 〈SiSi+1〉. As a result, we find that a creation of a singlet pair between both sides of the Mott core is strongly coupled with a pseudo-spin singlet re-formation leading to an energy gain process.

AB - We investigate a possibility of superfluidity in a trapped gas of Fermi atoms with repulsive interaction U in the presence of an optical lattice. Applying the exact diagonalization method to a one-dimensional fermion-Hubbard model including the trap potential, we find that, when U exceeds a critical value, the binding energy of two Fermi atoms becomes negative indicating that an attractive interaction effectively works. In this case, a "Mott core" appears in the trap center, where each site is occupied by one atom, and a large Cooper-pair amplitude develops between atoms in the left and right hand sides of this core. In order to clarify the origin of the attractive force, we compute a pseudo spin correlation between neighboring sites given by 〈SiSi+1〉. As a result, we find that a creation of a singlet pair between both sides of the Mott core is strongly coupled with a pseudo-spin singlet re-formation leading to an energy gain process.

KW - Atomic fermi gas

KW - Cooper pair

KW - Exact diagonalization

KW - Hubbard model

KW - Mott insulator

KW - Optical lattice

UR - http://www.scopus.com/inward/record.url?scp=33947532747&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33947532747&partnerID=8YFLogxK

U2 - 10.1063/1.2354607

DO - 10.1063/1.2354607

M3 - Conference contribution

AN - SCOPUS:33947532747

SN - 0735403473

SN - 9780735403475

VL - 850

SP - 61

EP - 62

BT - AIP Conference Proceedings

ER -