Bloch-sphere approach to correlated noise in coupled qubits

@article{Brox2012BlochsphereAT,
  title={Bloch-sphere approach to correlated noise in coupled qubits},
  author={H{\aa}kon Brox and Joakim Bergli and Yuri M. Galperin},
  journal={Journal of Physics A: Mathematical and Theoretical},
  year={2012},
  volume={45}
}
In order to demonstrate a generalized Bloch-sphere approach for the treatment of noise in coupled qubits, we perform a case study of the decoherence of a system composed of two interacting qubits in a noisy environment. In particular, we investigate the effects of correlations in the noise acting on distinct qubits. Our treatment of the two-qubit system by use of the generalized Bloch vector leads to tractable analytic equations for the dynamics of the four-level Bloch vector and allows for the… 

The dynamics of two entangled qubits exposed to classical noise: role of spatial and temporal noise correlations

TLDR
The decay of two-qubit entanglement caused by the influence of classical noise is investigated and is expressed in terms of expectation values of spherical tensor operators which allows for transparent insight into the role of the symmetry of both the two- qubit state and the noise forEntanglement dynamics.

Characterize noise correlation and enhance coherence via qubit motion

The identification of spacial noise correlation is of critical importance in developing error-corrected quantum devices, but it has barely been studied so far. In this work, we utilize an effective

Correlated versus uncorrelated noise acting on a quantum refrigerator

Two qubits form a quantum four-level system. The golden-rule based transition rates between these states are determined by the coupling of the qubits to noise sources. We demonstrate that depending

1 / f noise: Implications for solid-state quantum information

The efficiency of the future devices for quantum information processing will be limited mostly by the finite decoherence rates of the individual qubits and quantum gates. Recently, substantial

References

SHOWING 1-10 OF 47 REFERENCES

Decoherence of coupled Josephson charge qubits due to partially correlated low-frequency noise

Josephson charge qubits are promising candidates for scalable quantum computing. However, their performances are strongly degraded by decoherence due to low-frequency background noise, typically with

Decoherence in qubits due to low-frequency noise

The efficiency of the future devices for quantum information processing will be limited mostly by the finite decoherence rates of the qubits. Recently, substantial progress was achieved in enhancing

Effects of low-frequency noise cross-correlations in coupled superconducting qubits

We study the effects of correlated low-frequency noise sources acting on a two-qubit gate in a fixed coupling scheme. A decoherence model for the spatial and cross-talk correlations is introduced.

Low-Frequency Noise as a Source of Dephasing of a Qubit

With the growing efforts in isolating solid-state qubits from external decoherence sources, the material-inherent sources of noise start to play crucial role. One representative example is electron

Quantum oscillations in two coupled charge qubits

TLDR
This work demonstrates the feasibility of coupling multiple solid-state qubits, and indicates the existence of entangled two-qubit states, and demonstrates a Josephson circuit consisting of two coupled charge qubits.

Non-Gaussian low-frequency noise as a source of qubit decoherence.

TLDR
Decoherence in a qubit with the distance between the two levels affected by random flips of bistable fluctuators is studied with a resonant ac excitation and results significantly deviate from those obtained in the Gaussian model.

Coupled Josephson qubits: Characterization of low-frequency charge noise

Abstract.The realization of coupled qubit setups is a fundamental step towards implementation of universal quantum computing architectures. Solid state nano- devices, despite being very promising

Implementation of universal control on a decoherence-free qubit

We demonstrate storage and manipulation of one qubit encoded into a decoherence-free subspace (DFS) of two nuclear spins using liquid state nuclear magnetic resonance techniques. The DFS is spanned