Abstract
How to analytically deal with the entanglement and coherence dynamics of separated Jaynes–Cummings nodes with continuous-variable fields is still an open question. We here generalize this model to a more common situation including either a small or large qubit-field detuning, and obtain two new analytical formulas. The X-state simplification, Fock-state shortcut and detuning-limit approximation work together in an amazingly accurate way, which agrees with the numerical results. The new formulas almost perfectly predict the two-qubit entanglement dynamics both in sudden death and rebirth phenomenon for detuning interactions. We find that when both the qubit-field detuning and amplitude of coherent states are large enough, the maximal entanglement and coherence peaks can be fully and periodically retrieved, and their revival periods both increase linearly with the increasing detuning.
Highlights
Previous studies [5,14,20,29] have shown that the entanglement sudden death and rebirth appear in two separate Jaynes–Cummings nodes where two initial fields are both in the vacuum states, which are tough to generate and preserve due to decoherence in real experiments
It is significantly important to look for powerful field resources that can lead to the long-time generation and preservation of qubit entanglement and coherence
Based on numerical simulations and analytically new formulas, we demonstrate that the X-state simplification, Fock-state shortcut and detuning-limit approximation work together in an amazingly accurate way, which agrees with the numerical results
Summary
Qubit entanglement and coherence preservation are core issues in the fundamental theory and experiment of quantum optics and quantum information [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24]. One common continuous-variable resource is coherent state, which contains infinite eigenstate spectrums and can be controlled by a classical monochromatic current in real experiments [31,32] It can be solved directly through numerical diagonalization in a truncated Hilbert space, it is still difficult to obtain the analytical time-dependent dynamics when coupled to qubits due to the complexity of infinite-dimensional Hilbert space. Recent works [37,38] use an analytically novel method to prove that, even when the amplitudes of coherent-state fields are both large enough, the qubit entanglement dynamics of two resonant Jaynes–Cummings nodes can be explained by an exponentially decaying formula. The effect of dissipation factors on the qubit entanglement is considered
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
