Fermionization in an expanding 1D gas of hard-core bosons

Marcos Rigol; Alejandro Muramatsu

doi:10.1103/physrevlett.94.240403

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Fermionization in an expanding 1D gas of hard-core bosons

Marcos Rigol·Alejandro Muramatsu

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Abstract

We show by means of an exact numerical approach that the momentum distribution of a free expanding gas of hard-core bosons on a one-dimensional lattice approaches to the one of noninteracting fermions, acquiring a Fermi edge. Yet there is a power-law decay of the one-particle density matrix $ρ_x\sim 1/\sqrt{x}$, as usual for hard-core bosons in the ground state, which accounts for a large occupation of the lowest natural orbitals for all expansion times. The fermionization of the momentum distribution function, which is not observed in equilibrium, is analyzed in detail.

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Marcos Rigol, Alejandro Muramatsu. 2005-07-05. Fermionization in an expanding 1D gas of hard-core bosons. https://doi.org/10.1103/physrevlett.94.240403

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