Mixingdemixing transition and collapse of a vortex state in a quasitwodimensional bosonfermion mixture
Abstract
We investigate the mixingdemixing transition and the collapse in a quasitwodimensional degenerate bosonfermion mixture (DBFM) with a bosonic vortex. We solve numerically a quantumhydrodynamic model based on a new density functional which accurately takes into account the dimensional crossover. It is demonstrated that with the increase of interspecies repulsion, a mixed state of DBFM could turn into a demixed state. The system collapses for interspecies attraction above a critical value which depends on the vortex quantum number. For interspecies attraction just below this critical limit there is almost complete mixing of boson and fermion components. Such mixed and demixed states of a DBFM could be experimentally realized by varying an external magnetic field near a bosonfermion Feshbach resonance, which will result in a continuous variation of interspecies interaction.
 Authors:
 Instituto de Fisica Teorica, UNESPSao Paulo State University, 01.405900 Sao Paulo, Sao Paulo (Brazil)
 CNISM and CNRINFM, Unita di Padova, Dipartimento di Fisica 'Galileo Galilei', Universita di Padova, Via Marzolo 8, 35131 Padova (Italy)
 Publication Date:
 OSTI Identifier:
 20982563
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.053603; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; BOSONS; DENSITY FUNCTIONAL METHOD; FERMIONS; HYDRODYNAMIC MODEL; INTERACTIONS; MAGNETIC FIELDS; MATHEMATICAL MODELS; MIXED STATE; NUMERICAL SOLUTION; RESONANCE; TWODIMENSIONAL CALCULATIONS; VORTICES
Citation Formats
Adhikari, Sadhan K., and Salasnich, Luca. Mixingdemixing transition and collapse of a vortex state in a quasitwodimensional bosonfermion mixture. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.053603.
Adhikari, Sadhan K., & Salasnich, Luca. Mixingdemixing transition and collapse of a vortex state in a quasitwodimensional bosonfermion mixture. United States. doi:10.1103/PHYSREVA.75.053603.
Adhikari, Sadhan K., and Salasnich, Luca. Tue .
"Mixingdemixing transition and collapse of a vortex state in a quasitwodimensional bosonfermion mixture". United States.
doi:10.1103/PHYSREVA.75.053603.
@article{osti_20982563,
title = {Mixingdemixing transition and collapse of a vortex state in a quasitwodimensional bosonfermion mixture},
author = {Adhikari, Sadhan K. and Salasnich, Luca},
abstractNote = {We investigate the mixingdemixing transition and the collapse in a quasitwodimensional degenerate bosonfermion mixture (DBFM) with a bosonic vortex. We solve numerically a quantumhydrodynamic model based on a new density functional which accurately takes into account the dimensional crossover. It is demonstrated that with the increase of interspecies repulsion, a mixed state of DBFM could turn into a demixed state. The system collapses for interspecies attraction above a critical value which depends on the vortex quantum number. For interspecies attraction just below this critical limit there is almost complete mixing of boson and fermion components. Such mixed and demixed states of a DBFM could be experimentally realized by varying an external magnetic field near a bosonfermion Feshbach resonance, which will result in a continuous variation of interspecies interaction.},
doi = {10.1103/PHYSREVA.75.053603},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

Mixingdemixing transition in onedimensional mixtures of fermions and bosons is numerically investigated by changing various parameters such as number densities of each component, fermionboson interactions, bosonboson interactions, and hopping energies. In most cases we found clear evidence of the mixingdemixing transitions and identified the roles of each microscopic parameter in the transitions. Several phase diagrams were obtained.


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