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Readout methods and devices for Josephson-junction-based solid-state qubits

G. Johansson·L. Tornberg·V. S. Shumeiko·G. Wendin
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Abstract

We discuss the current situation concerning measurement and readout of Josephson-junction based qubits. In particular we focus attention of dispersive low-dissipation techniques involving reflection of radiation from an oscillator circuit coupled to a qubit, allowing single-shot determination of the state of the qubit. In particular we develop a formalism describing a charge qubit read out by measuring its effective (quantum) capacitance. To exemplify, we also give explicit formulas for the readout time.

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G. Johansson, L. Tornberg, V. S. Shumeiko, G. Wendin. 2006-02-24. Readout methods and devices for Josephson-junction-based solid-state qubits. https://doi.org/10.1088/0953-8984%2F18%2F21%2Fs14

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