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arXiv · 1704.05876

Quantum-limited measurement of spin qubits via curvature coupling to a cavity

Rusko Ruskov·Charles Tahan
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Abstract

We investigate coupling an encoded spin qubit to a microwave resonator via qubit energy level curvature versus gate voltage. This approach enables quantum non-demolition readout with strength of tens to hundred MHz all while the qubit stays at its full sweet-spot to charge noise, with zero dipole moment. A "dispersive-like" spin readout approach similar to circuit-QED but avoiding the Purcell effect is proposed. With the addition of gate voltage modulation, selective longitudinal readout and n-qubit entanglement-by-measurement are possible.

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Rusko Ruskov, Charles Tahan. 2017-04-19. Quantum-limited measurement of spin qubits via curvature coupling to a cavity. https://doi.org/10.1103/physrevb.99.245306

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