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

arXiv:1903.03329 · Communications in Theoretical Physics

Complementarity between micro-micro and micro-macro entanglement in a Bose–Einstein condensate with two Rydberg impurities

Zhen Li, Yu Han, Le-Man Kuang

Published Jan 22, 2020• 6 citations
arXivHTMLPDF

Abstract

Abstract We theoretically study complementarity between micro-micro and micro-macro entanglement in a Bose–Einstein condensate with two Rydberg impurities. We investigate quantum dynamics of micro-micro and micro-macro entanglement in the micro-macro system. It is found that strong micro-macro entanglement between Rydberg impurities and the BEC can be generated by the use of initial micro-micro entanglement between two Rydberg impurities, which acts as the seed entanglement to create micro-macro entanglement. We demonstrate a curious complementarity relation between micro-micro and micro-macro entanglement, and find that the complementarity property can be sustained to some extent even though in the presence of the BEC decoherence.

DOI
10.1088/1572-9494/ab6182

Related papers

Witnessing entanglement via the geometric phase in a impurity-doped Bose-Einstein condensate

Xuntao Wu, Shao-Peng Jia, Cai, C. L. +1 more

We propose a theoretical scheme to witness quantum entanglement via the geometric phase in an impurity-doped Bose-Einstein condensate (BEC), which is a micro-macro quantum system consisting of two Rydberg impurity qubits and the BEC. We calculate the geometric phase of the impurity qubits in the presence of the initial micro-micro and micro-macro entanglement, respectively. It is demonstrated that the geometric phase of the impurity qubits can witness not only inter-qubit micro-micro entanglement, but also qubit-BEC micro-macro entanglement. Our work provide a new insight to witness micro-micro and micro-macro entanglement in a impurity-doped BEC.

arXiv:2106.00224•Jun 1, 2021•0 citations

Quantum dynamics of an impurity-doped Bose–Einstein condensate system

Yu Han, Li Zhen, Le‐Man Kuang

Abstract We study the quantum dynamics of an impurity-doped Bose–Einstein condensate (BEC) system. We show how to generate the macroscopic quantum superposition states (MQSSs) of the BEC by the use of projective measurements on impurity atoms. It is found that the nonclassicality of MQSSs can be manipulated by changing the number of the impurities and their interaction with the BEC. It is shown that the BEC matter-wave field exhibits a collapse and revival phenomenon which reveals the quantum nature of the BEC matter-wave field. We investigate the micro-macro entanglement between the impurities and the BEC, and find enhancement of the micro-macro entanglement induced by the initial quantum coherence of the impurity atoms.

Communications in Theoretical Physics•Aug 27, 2020•3 citations

Rydberg impurities control and probe superpositions of Bose-Einstein Condensates

S. Rammohan, Shiva Kant Tiwari, Adya Prasad Mishra +5 more

We show that two major facets of the decoherence paradigm are experimentally accessible for a single impurity atom embedded in a Bose-Einstein condensate, when the impurity is brought into an electronic superposition of two Rydberg states. Not only can the electronic decoherence of the Rydberg atom be read out by microwave interferometry, the platform also provides unique access to the accompanying entangled state of the environment. We theoretically demonstrate signatures of the latter in total atom densities during the transient time in which the impurity is becoming entangled with the medium but the resultant decoherence is not complete yet. The Rydberg impurity thus provides a handle to initiate and read-out mesoscopically entangled superposition states of Bose atom clouds affecting about 500 condensate atoms. We find that the time-scale for its creation and decoherence can be tuned from the order of nanoseconds to microseconds by choice of the excited Rydberg principal quantum number $\nu$, and that Rydberg decoherence dynamics is typically non- Markovian.

•Nov 22, 2020•0 citations

Entanglement generation between spinor Bose-Einstein condensates using Rydberg excitations

Sandrine Idlas, Luis Domenzain, R. J. C. Spreeuw +1 more

We propose an experimental scheme of generating entangled states between two spinor Bose-Einstein condensates (BECs) using Rydberg excitations. Due to the strong interaction between Rydberg atoms, the Rydberg excitation creates an interaction between two closely located BECs. The method is suitable particularly for atom chip and permanent magnetic trap systems, which can create many BECs with an arbitrary two-dimensional geometry. We show two schemes of entangled state generation, based on stimulated Raman adiabatic passage (STIRAP) methods. The first method produces a symmetric state with total ${S}^{x}$ spin zero between ground and excited states of the atoms using a single STIRAP pair, while the second produces a NOON state between hyperfine ground states using two STIRAP pairs. We show that despite the additional complexity of the BECs, it is possible to identify the initial and final adiabatic states exactly. We verify our theoretical predictions using numerical simulations on small boson number systems.

Physical Review A•Feb 12, 2016•19 citations

Quantum Dynamics of Cavity–Bose–Einstein Condensates in a Gravitational Field

Zhen Li, Wangjun Lu, Ya‐Feng Jiao

We theoretically studied the quantum dynamics of a cavity–Bose–Einstein condensate (BEC) system in a gravitational field, which is composed of a Fabry–Pérot cavity and a BEC. We also show how to deterministically generate the transient macroscopic quantum superposition states (MQSSs) of the cavity by the use of optomechanical coupling between the cavity field and the BEC. The quantum dynamics of the cavity–BEC system specifically include phase space trajectory dynamics, system excitation number dynamics, quantum entanglement dynamics, and quantum coherence dynamics. We found that the system performs increasingly complex trajectories for larger values of the Newtonian gravity parameter. Moreover, the number of phonon excitations of the system can be increased by coupling the cavity–BEC system to Newtonian gravity, which is analogous to an external direct current drive. The scattering of atoms inside the BEC affects the periodicity of the quantum dynamics of the system. We demonstrate a curious complementarity relation between the quantum entanglement and quantum coherence of cavity–BEC systems and found that the complementarity property can be sustained to some extent, despite being in the presence of the cavity decay. This phenomenon also goes some way to show that quantum entanglement and quantum coherence can be referred to together as quantum resources.

Photonics•Feb 24, 2024•1 citation

Dynamics, dephasing and clustering of impurity atoms in Bose–Einstein condensates

Alexander Klein, Martin Bruderer, Stephen R Clark +1 more

We investigate the influence of a Bose–Einstein condensate (BEC) on the properties of immersed impurity atoms, which are trapped in an optical lattice. Assuming a weak coupling of the impurity atoms to the BEC, we derive a quantum master equation (QME) for the lattice system. In the special case of fixed impurities with two internal states the atoms represent a quantum register and the QME reproduces the exact evolution of the qubits. We characterize the qubit dephasing which is caused by the interspecies coupling and show that the effect of sub- and super-decoherence is observable for realistic experimental parameters. Furthermore, the BEC phonons mediate an attractive interaction between the impurities, which has an important impact on their spatial distribution. If the lattice atoms are allowed to move, there occurs a sharp transition with the impurities aggregating in a macroscopic cluster at experimentally achievable temperatures. We also investigate the impact of the BEC on the transport properties of the impurity atoms and show that a crossover from coherent to diffusive behaviour occurs with increasing interaction strength.

arXiv:0710.3539•New Journal of Physics•Nov 21, 2007•70 citations
Abstract We theoretically study complementarity between micro-micro and micro-macro entanglement in a Bose–Einstein condensate with two Rydberg impurities. We investigate quantum dynamics of micro-micro and micro-macro entanglement in the micro-macro system. It is found that strong micro-macro entanglement between Rydberg impurities and the BEC can be generated by the use of initial micro-micro entanglement between two Rydberg impurities, which acts as the seed entanglement to create micro-macro entanglement. We demonstrate a curious complementarity relation between micro-micro and micro-macro entanglement, and find that the complementarity property can be sustained to some extent even though in the presence of the BEC decoherence.
We propose a theoretical scheme to witness quantum entanglement via the geometric phase in an impurity-doped Bose-Einstein condensate (BEC), which is a micro-macro quantum system consisting of two Rydberg impurity qubits and the BEC. We calculate the geometric phase of the impurity qubits in the presence of the initial micro-micro and micro-macro entanglement, respectively. It is demonstrated that the geometric phase of the impurity qubits can witness not only inter-qubit micro-micro entanglement, but also qubit-BEC micro-macro entanglement. Our work provide a new insight to witness micro-micro and micro-macro entanglement in a impurity-doped BEC.
Abstract We study the quantum dynamics of an impurity-doped Bose–Einstein condensate (BEC) system. We show how to generate the macroscopic quantum superposition states (MQSSs) of the BEC by the use of projective measurements on impurity atoms. It is found that the nonclassicality of MQSSs can be manipulated by changing the number of the impurities and their interaction with the BEC. It is shown that the BEC matter-wave field exhibits a collapse and revival phenomenon which reveals the quantum nature of the BEC matter-wave field. We investigate the micro-macro entanglement between the impurities and the BEC, and find enhancement of the micro-macro entanglement induced by the initial quantum coherence of the impurity atoms.
We show that two major facets of the decoherence paradigm are experimentally accessible for a single impurity atom embedded in a Bose-Einstein condensate, when the impurity is brought into an electronic superposition of two Rydberg states. Not only can the electronic decoherence of the Rydberg atom be read out by microwave interferometry, the platform also provides unique access to the accompanying entangled state of the environment. We theoretically demonstrate signatures of the latter in total atom densities during the transient time in which the impurity is becoming entangled with the medium but the resultant decoherence is not complete yet. The Rydberg impurity thus provides a handle to initiate and read-out mesoscopically entangled superposition states of Bose atom clouds affecting about 500 condensate atoms. We find that the time-scale for its creation and decoherence can be tuned from the order of nanoseconds to microseconds by choice of the excited Rydberg principal quantum number ν\nuν, and that Rydberg decoherence dynamics is typically non- Markovian.
We propose an experimental scheme of generating entangled states between two spinor Bose-Einstein condensates (BECs) using Rydberg excitations. Due to the strong interaction between Rydberg atoms, the Rydberg excitation creates an interaction between two closely located BECs. The method is suitable particularly for atom chip and permanent magnetic trap systems, which can create many BECs with an arbitrary two-dimensional geometry. We show two schemes of entangled state generation, based on stimulated Raman adiabatic passage (STIRAP) methods. The first method produces a symmetric state with total Sx{S}^{x}Sx spin zero between ground and excited states of the atoms using a single STIRAP pair, while the second produces a NOON state between hyperfine ground states using two STIRAP pairs. We show that despite the additional complexity of the BECs, it is possible to identify the initial and final adiabatic states exactly. We verify our theoretical predictions using numerical simulations on small boson number systems.
We theoretically studied the quantum dynamics of a cavity–Bose–Einstein condensate (BEC) system in a gravitational field, which is composed of a Fabry–Pérot cavity and a BEC. We also show how to deterministically generate the transient macroscopic quantum superposition states (MQSSs) of the cavity by the use of optomechanical coupling between the cavity field and the BEC. The quantum dynamics of the cavity–BEC system specifically include phase space trajectory dynamics, system excitation number dynamics, quantum entanglement dynamics, and quantum coherence dynamics. We found that the system performs increasingly complex trajectories for larger values of the Newtonian gravity parameter. Moreover, the number of phonon excitations of the system can be increased by coupling the cavity–BEC system to Newtonian gravity, which is analogous to an external direct current drive. The scattering of atoms inside the BEC affects the periodicity of the quantum dynamics of the system. We demonstrate a curious complementarity relation between the quantum entanglement and quantum coherence of cavity–BEC systems and found that the complementarity property can be sustained to some extent, despite being in the presence of the cavity decay. This phenomenon also goes some way to show that quantum entanglement and quantum coherence can be referred to together as quantum resources.
We investigate the influence of a Bose–Einstein condensate (BEC) on the properties of immersed impurity atoms, which are trapped in an optical lattice. Assuming a weak coupling of the impurity atoms to the BEC, we derive a quantum master equation (QME) for the lattice system. In the special case of fixed impurities with two internal states the atoms represent a quantum register and the QME reproduces the exact evolution of the qubits. We characterize the qubit dephasing which is caused by the interspecies coupling and show that the effect of sub- and super-decoherence is observable for realistic experimental parameters. Furthermore, the BEC phonons mediate an attractive interaction between the impurities, which has an important impact on their spatial distribution. If the lattice atoms are allowed to move, there occurs a sharp transition with the impurities aggregating in a macroscopic cluster at experimentally achievable temperatures. We also investigate the impact of the BEC on the transport properties of the impurity atoms and show that a crossover from coherent to diffusive behaviour occurs with increasing interaction strength.