Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Physics B Atomic Molecular and Optical Physics

Swapping of natural entanglement in the ground state of the Fermi gas mixture

Leonid V. Il'ichov

Published Oct 14, 2009• 0 citations
Publisher

Abstract

The paper considers the role of spin correlation swapping in spatial correlations between recombination events in a mixture of two ground-state Fermi gases. A simple geometrical structure of swapping transformation of the spin correlations was found and used. The results seem to be useful for studies of structure and the evolution of spin correlations under localized events of particle conversions in extended quantum systems.

DOI
10.1088/0953-4075/42/21/215304

Related papers

Spatial bunching and antibunching of recombination events in a fermionic medium with pair quantum correlations

L. V. Il’ichev, S. V. Anishchik

The spatial correlation of recombination events is considered for the model quantum state composed of singlet fermion pairs. The competition between the Fermi statistics, which leads to the antibunching of the events, and the entanglement transfer, which causes the tendency of the bunching of the events, is revealed.

Journal of Experimental and Theoretical Physics Letters•Jan 1, 2008•2 citations

Binary mixture of pseudo-spin- 12 Bose gases with interspecies spin exchange: From classical fixed points and ground states to quantum ground states

Rukuan Wu, Yu Shi

We consider the effective spin Hamiltonian describing a mixture of two species of pseudo-spin-$\frac{1}{2}$ Bose gases with interspecies spin exchange. First we analyze the stability of the fixed points of the corresponding classical dynamics, of which the signature is found in quantum dynamics with a disentangled initial state. Focusing on the case without an external potential, we find all the ground states by taking into account quantum fluctuations around the classical ground state in each parameter regime. The nature of entanglement and its relation with classical bifurcation is investigated. When the total spins of the two species are unequal, the maximal entanglement at the parameter point of classical bifurcation is possessed by the excited state corresponding to the classical fixed point which bifurcates, rather than by the ground state.

arXiv:1112.2852•Physical Review A•Dec 7, 2011•4 citations

Ground states of a mixture of two species of spinor Bose gases with interspecies spin exchange

Yu Shi

We consider a mixture of two species of spin-1 atoms with interspecies spin exchange, which may cooperate or compete with intraspecies spin exchanges and thus dramatically affect the ground state. It represents a new class of bosonic gases differing from single-species spinor gases. We determine the exact ground states in several parameter regimes and study the composite structures using the generating function method generalized here to be applicable to a mixture of two species of spinor gases. The most interesting phase is the so-called entangled Bose-Einstein condensation (BEC), which is fragmented BEC with quantum entanglement between the two species and with both interspecies and intraspecies singlet pairs. For comparison, we also apply the generating function method to a mixture of two species of pseudospin-$\frac{1}{2}$ atoms, for which the total spin quantum number of each species is fixed as half of the atom number, in contrast with the case of spin $1$, for which it is a variable determined by energetics. Consequently, singlet pairs in entangled BEC of a pseudospin-$\frac{1}{2}$ mixture are all interspecies. Interspecies spin exchange leads to novel features beyond those of spinor BEC of a single species of atoms as well as mixtures without interspecies spin exchange.

arXiv:0912.2209•Physical Review A•Aug 5, 2010•24 citations

Ground State of Bose–Fermi Mixture with Spin–Orbit Coupling

Ryohei Sakamoto, Yosuke Ono, Emiko Arahata +1 more

We study a mixture of Bose and Fermi gases with equal Rashba and Dresselhaus spin–orbit coupling. The phase diagram of bosons with the same coupling was already studied in a mean-field approximation and shown to have three kinds of ground states. In the present study, the ground state of the spin–orbit coupled Bose–Fermi mixture is investigated in the same approach to analyze effects of introducing fermions to the bosonic system. The result shows that even a small amount of fermions could drastically change the phase diagram of the bosons.

Journal of the Physical Society of Japan•May 9, 2016•3 citations

Swapping of Quantum Correlations and the Role of Local Filtering Operations

Pedro Rosário, Andrés F. Ducuara, Cristian E. Susa

Abstract The swapping of various quantum correlation measures is addressed including, Bell‐nonlocality, Einstein–Podolsky–Rosen steering, usefulness for teleportation, and entanglement, as well as quantum obesity as a quantum correlation more general than entanglement. The effects that local filtering operations have on the swapping of such correlations are particularly focused. Based on a generalization of entanglement swapping with arbitrary two‐qubit states and arbitrary measurements, analytical formulae for the swapping of two‐qudit as well as multi‐qubit quantum states are derived and the exact amount of quantum obesity that is swapped is provided. Then, in order to enhance the final amount of correlations in the post‐swapping two‐qubit state, the action of local filters before as well as after the swapping protocol is explored. In this regard, it is conjectured that applying local filters first is more efficient. This is supported by an analytical proof on the quantum obesity of almost Bell‐diagonal states, as well as numerical evidence for all the considered quantum correlations of arbitrary X‐form states.

arXiv:2307.16524•Advanced Quantum Technologies•Jun 4, 2025•2 citations

Density-functional theory of two-component Bose gases in one-dimensional harmonic traps

Yajiang Hao, Shu Chen

We investigate the ground-state properties of two-component Bose gases confined in one-dimensional harmonic traps in the scheme of density-functional theory. The density-functional calculations employ a Bethe-ansatz-based local-density approximation for the correlation energy, which accounts for the correlation effect properly from the weakly interacting regime to the strongly interacting regime. For the binary Bose mixture with spin-independent interaction, the homogeneous reference system is exactly solvable by the Bethe-ansatz method. Within the local-density approximation, we determine the density distribution of each component and study its evolution from Bose distributions to Fermi-like distribution with the increase in interaction. For the binary mixture of Tonks-Girardeau gases with a tunable interspecies repulsion, with a generalized Bose-Fermi transformation we show that the Bose mixture can be mapped into a two-component Fermi gas, which corresponds to exact soluble Yang-Gaudin model for the homogeneous system. Based on the ground-state energy function of the Yang-Gaudin model, the ground-state density distributions are calculated for various interspecies interactions. It is shown that with the increase in interspecies interaction, the system exhibits composite-fermionization crossover.

arXiv:0905.3207•Physical Review A•Oct 14, 2009•34 citations
The paper considers the role of spin correlation swapping in spatial correlations between recombination events in a mixture of two ground-state Fermi gases. A simple geometrical structure of swapping transformation of the spin correlations was found and used. The results seem to be useful for studies of structure and the evolution of spin correlations under localized events of particle conversions in extended quantum systems.
We consider the effective spin Hamiltonian describing a mixture of two species of pseudo-spin-12\frac{1}{2}21​ Bose gases with interspecies spin exchange. First we analyze the stability of the fixed points of the corresponding classical dynamics, of which the signature is found in quantum dynamics with a disentangled initial state. Focusing on the case without an external potential, we find all the ground states by taking into account quantum fluctuations around the classical ground state in each parameter regime. The nature of entanglement and its relation with classical bifurcation is investigated. When the total spins of the two species are unequal, the maximal entanglement at the parameter point of classical bifurcation is possessed by the excited state corresponding to the classical fixed point which bifurcates, rather than by the ground state.
We consider a mixture of two species of spin-1 atoms with interspecies spin exchange, which may cooperate or compete with intraspecies spin exchanges and thus dramatically affect the ground state. It represents a new class of bosonic gases differing from single-species spinor gases. We determine the exact ground states in several parameter regimes and study the composite structures using the generating function method generalized here to be applicable to a mixture of two species of spinor gases. The most interesting phase is the so-called entangled Bose-Einstein condensation (BEC), which is fragmented BEC with quantum entanglement between the two species and with both interspecies and intraspecies singlet pairs. For comparison, we also apply the generating function method to a mixture of two species of pseudospin-12\frac{1}{2}21​ atoms, for which the total spin quantum number of each species is fixed as half of the atom number, in contrast with the case of spin 111, for which it is a variable determined by energetics. Consequently, singlet pairs in entangled BEC of a pseudospin-12\frac{1}{2}21​ mixture are all interspecies. Interspecies spin exchange leads to novel features beyond those of spinor BEC of a single species of atoms as well as mixtures without interspecies spin exchange.
We study a mixture of Bose and Fermi gases with equal Rashba and Dresselhaus spin–orbit coupling. The phase diagram of bosons with the same coupling was already studied in a mean-field approximation and shown to have three kinds of ground states. In the present study, the ground state of the spin–orbit coupled Bose–Fermi mixture is investigated in the same approach to analyze effects of introducing fermions to the bosonic system. The result shows that even a small amount of fermions could drastically change the phase diagram of the bosons.
Abstract The swapping of various quantum correlation measures is addressed including, Bell‐nonlocality, Einstein–Podolsky–Rosen steering, usefulness for teleportation, and entanglement, as well as quantum obesity as a quantum correlation more general than entanglement. The effects that local filtering operations have on the swapping of such correlations are particularly focused. Based on a generalization of entanglement swapping with arbitrary two‐qubit states and arbitrary measurements, analytical formulae for the swapping of two‐qudit as well as multi‐qubit quantum states are derived and the exact amount of quantum obesity that is swapped is provided. Then, in order to enhance the final amount of correlations in the post‐swapping two‐qubit state, the action of local filters before as well as after the swapping protocol is explored. In this regard, it is conjectured that applying local filters first is more efficient. This is supported by an analytical proof on the quantum obesity of almost Bell‐diagonal states, as well as numerical evidence for all the considered quantum correlations of arbitrary X‐form states.
We investigate the ground-state properties of two-component Bose gases confined in one-dimensional harmonic traps in the scheme of density-functional theory. The density-functional calculations employ a Bethe-ansatz-based local-density approximation for the correlation energy, which accounts for the correlation effect properly from the weakly interacting regime to the strongly interacting regime. For the binary Bose mixture with spin-independent interaction, the homogeneous reference system is exactly solvable by the Bethe-ansatz method. Within the local-density approximation, we determine the density distribution of each component and study its evolution from Bose distributions to Fermi-like distribution with the increase in interaction. For the binary mixture of Tonks-Girardeau gases with a tunable interspecies repulsion, with a generalized Bose-Fermi transformation we show that the Bose mixture can be mapped into a two-component Fermi gas, which corresponds to exact soluble Yang-Gaudin model for the homogeneous system. Based on the ground-state energy function of the Yang-Gaudin model, the ground-state density distributions are calculated for various interspecies interactions. It is shown that with the increase in interspecies interaction, the system exhibits composite-fermionization crossover.