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Robustness of Decoherence-Free States for Charge Qubits under Local Non-uniformity

Tetsufumi Tanamoto·Shinobu Fujita
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Abstract

We analyze the robustness of decoherence-free (DF) subspace and subsystem in charge qubits, when difference from the collective decoherence measurement condition is large in the long time period, which is applicable for solid-state qubits using as a quantum memory. We solve master equations of up to four charge qubits and a detector as a quantum point contact (QPC). We show that robustness of DF states is strongly affected by local non-uniformities. We also discuss the possible two-qubit logical states by exactly solving the master equations.

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Tetsufumi Tanamoto, Shinobu Fujita. 2004-12-27. Robustness of Decoherence-Free States for Charge Qubits under Local Non-uniformity. https://doi.org/10.1103/physrevb.72.085335

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