Controlling dephasing of coupled qubits via shared-bath coherence
- URL: http://arxiv.org/abs/2405.14685v1
- Date: Thu, 23 May 2024 15:22:30 GMT
- Title: Controlling dephasing of coupled qubits via shared-bath coherence
- Authors: L. M. J. Hall, L. S. Sirkina, A. Morreau, W. Langbein, E. A. Muljarov,
- Abstract summary: We show that the decoherence of a coupled qubit system can be minimized, or even eliminated by exploiting the quantum coherence of the bath itself.
We investigate the dephasing in a system of two spatially separated, electronically decoupled qubits, with direct or mediated coupling.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The interaction of a quantum system with its environment limits qubit coherence times and restricts its utility in quantum information processing applications. In this Letter, we show that the decoherence of a coupled qubit system can be minimized, or even eliminated by exploiting the quantum coherence of the bath itself. We investigate the dephasing in a system of two spatially separated, electronically decoupled qubits, with direct or mediated coupling, interacting with a shared bath. For illustration we treat F\"orster or cavity-mediated coupling between semiconductor quantum dots interacting with acoustic phonons. Using the rigorous method of Trotter's decomposition with cumulant expansion, we demonstrate a reduction in the dephasing rates at specific distances. This control is a coherent effect of the shared bath and is absent for independent baths. It can be understood in terms of phonon-assisted transitions between the entangled qubit states of the coupled system.
Related papers
- Entanglement and operator correlation signatures of many-body quantum Zeno phases in inefficiently monitored noisy systems [49.1574468325115]
The interplay between information-scrambling Hamiltonians and local continuous measurements hosts platforms for exotic measurement-induced phase transition.
We identify a non-monotonic dependence on the local noise strength in both the averaged entanglement and operator correlations.
The analysis of scaling with the system size in a finite length chain indicates that, at finite efficiency, this effect leads to distinct MiPTs for operator correlations and entanglement.
arXiv Detail & Related papers (2024-07-16T13:42:38Z) - Entanglement preservation in tripartite quantum systems under dephasing
dynamics [0.0]
We investigate the tripartite entanglement dynamics of pure and mixed states in the presence of a structured dephasing environment at finite temperature.
We show that the robustness of the quantum system to decoherence is dependent on the distribution of entanglement.
The sustainability of tripartite entanglement is shown to be enhanced significantly in presence of reservoir memory.
arXiv Detail & Related papers (2023-11-09T06:19:08Z) - Correlated noise enhances coherence and fidelity in coupled qubits [5.787049285733455]
Noise correlation can enhance the fidelity and purity of a maximally entangled (Bell) state.
These observations may be useful in the design of high-fidelity quantum gates and communication protocols.
arXiv Detail & Related papers (2023-08-01T21:13:35Z) - Dephasing effects on quantum correlations and teleportation in presence
of state dependent bath [0.0]
We analyze the effect of state dependent bath on the quantum correlations and the fidelity of a single qubit teleportation.
It is shown that due to the presence of initial system-bath correlations, the system maintains quantum correlations for long times.
arXiv Detail & Related papers (2023-07-03T15:31:19Z) - Entanglement and localization in long-range quadratic Lindbladians [49.1574468325115]
Signatures of localization have been observed in condensed matter and cold atomic systems.
We propose a model of one-dimensional chain of non-interacting, spinless fermions coupled to a local ensemble of baths.
We show that the steady state of the system undergoes a localization entanglement phase transition by tuning $p$ which remains stable in the presence of coherent hopping.
arXiv Detail & Related papers (2023-03-13T12:45:25Z) - Bell inequalities with overlapping measurements [52.81011822909395]
We study Bell inequalities where measurements of different parties can have overlap.
This allows to accommodate problems in quantum information.
The scenarios considered show an interesting behaviour with respect to Hilbert space dimension, overlap, and symmetry.
arXiv Detail & Related papers (2023-03-03T18:11:05Z) - Nonadiabatic quantum control of quantum dot arrays with fixed exchange
using Cartan decomposition [0.0]
In semiconductor spin qubits, shuttling of spin is a practical way to generate quantum operations between distant qubits.
We extend our previous results for double- and triple-dot systems, and describe a method for implementing spin shuttling in long chains of quantum dots in a nonadiabatic manner.
arXiv Detail & Related papers (2022-07-06T01:04:39Z) - Impact of independent reservoirs on the quantum Zeno and anti-Zeno
effects [0.5801044612920815]
We look at what happens to a quantum system if it interacts with two independent reservoirs.
We show that the presence of the strongly coupled reservoir can actually reduce the decay rate of the quantum system due to the effect of the weakly-coupled reservoir.
arXiv Detail & Related papers (2020-12-10T10:43:34Z) - Continuous and time-discrete non-Markovian system-reservoir
interactions: Dissipative coherent quantum feedback in Liouville space [62.997667081978825]
We investigate a quantum system simultaneously exposed to two structured reservoirs.
We employ a numerically exact quasi-2D tensor network combining both diagonal and off-diagonal system-reservoir interactions with a twofold memory for continuous and discrete retardation effects.
As a possible example, we study the non-Markovian interplay between discrete photonic feedback and structured acoustic phononovian modes, resulting in emerging inter-reservoir correlations and long-living population trapping within an initially-excited two-level system.
arXiv Detail & Related papers (2020-11-10T12:38:35Z) - Realization of high-fidelity CZ and ZZ-free iSWAP gates with a tunable
coupler [40.456646238780195]
Two-qubit gates at scale are a key requirement to realize the full promise of quantum computation and simulation.
We present a systematic approach that goes beyond the dispersive approximation to exploit the engineered level structure of the coupler and optimize its control.
We experimentally demonstrate CZ and $ZZ$-free iSWAP gates with two-qubit interaction fidelities of $99.76 pm 0.07$% and $99.87 pm 0.23$%, respectively.
arXiv Detail & Related papers (2020-11-02T19:09:43Z) - Universal non-adiabatic control of small-gap superconducting qubits [47.187609203210705]
We introduce a superconducting composite qubit formed from two capacitively coupled transmon qubits.
We control this low-frequency CQB using solely baseband pulses, non-adiabatic transitions, and coherent Landau-Zener interference.
This work demonstrates that universal non-adiabatic control of low-frequency qubits is feasible using solely baseband pulses.
arXiv Detail & Related papers (2020-03-29T22:48:34Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.