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DOE OSTI · 21529039

Quantum memories based on engineered dissipation

Pastawski, Fernando·Clemente, Lucas·Cirac, Juan Ignacio
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Abstract

Storing quantum information for long times without disruptions is a major requirement for most quantum information technologies. A very appealing approach is to use self-correcting Hamiltonians, that is tailoring local interactions among the qubits such that when the system is weakly coupled to a cold bath the thermalization process takes a long time. Here we propose an alternative but more powerful approach in which the coupling to a bath is engineered, so that dissipation protects the encoded qubit against more general kinds of errors. We show that the method can be implemented locally in four-dimensional lattice geometries by means of a toric code and propose a simple two-dimensional setup for proof-of-principle experiments.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSCOUPLINGERRORSFOUR-DIMENSIONAL CALCULATIONSGEOMETRYHAMILTONIANSINFORMATIONINTERACTIONSMATHEMATICAL OPERATORSMATHEMATICSQUANTUM INFORMATIONQUANTUM OPERATORSQUBITSSLOWING-DOWNTHERMALIZATIONTWO-DIMENSIONAL CALCULATIONS

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Pastawski, Fernando, Clemente, Lucas, Cirac, Juan Ignacio. 2011-01-15. Quantum memories based on engineered dissipation. https://doi.org/10.1103/physreva.83.012304

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