Mesoscopic d-Wave Qubits: Can High-Tc Cuprates Play a Role in Quantum Computing?

A. M. Zagoskin

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Mesoscopic d-Wave Qubits: Can High-Tc Cuprates Play a Role in Quantum Computing?

A. M. Zagoskin

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Abstract

Due to nontrivial orbital pairing symmetry, surfaces and interfaces of high-Tc superconductors sup- port states which violate time-reversal (T -) symmetry. Such naturally degenerate states, useful as work- ing states of a qubit, are standard for atomic or molecular-size qubit prototypes (e.g. based on nuclear spins), but exceptional for mesoscopic qubits. (In particular, they hold promise of a better scalability.) In these lectures I review the physics of T -breaking on surfaces and interfaces of high-Tc superconductors; then describe existing proposals for high-Tc based qubits and the current state of experiments; Finally, I discuss the decoherence sources in the system, open questions, and future research directions.

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A. M. Zagoskin. 2005-06-02. Mesoscopic d-Wave Qubits: Can High-Tc Cuprates Play a Role in Quantum Computing?. https://arxiv.org/abs/cond-mat/0506039

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