Quantum Noise in the Josephson Charge Qubit

2004/11/09 by O. Astafiev, O. V. Astafiev, Yu. A. Pashkin +5 · 3 citations
Computer Science · Physics and Astronomy · #Charge (physics) #Charge qubit #Cold Atom Physics and Bose-Einstein Condensates #Dephasing #Flux qubit #Josephson effect #Noise (video) #Phase qubit #Physics #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum decoherence #Quantum mechanics #Quantum noise #Qubit #Relaxation (psychology) #Superconductivity #cond-mat.mes-hall #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevlett.93.267007

published as Phys. Rev. Lett. 93, 267007 (2004) · Submitted to Phys. Rev. Letters

arxiv created 2004/11/09 · openalex publication_date 2004/12/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We study decoherence of the Josephson charge qubit by measuring energy relaxation and dephasing with help of the single-shot readout. We found that the dominant energy relaxation process is a spontaneous emission induced by quantum noise coupled to the charge degree of freedom. Spectral density of the noise at high frequencies is roughly proportional to the qubit excitation energy.

Citations

• Coherent control of macroscopic quantum states in a single-Cooper-pair box
• Coherent Quantum Dynamics of a Superconducting Flux Qubit
• Demonstration of conditional gate operation using superconducting charge qubits
• Coherent dynamics of a Josephson charge qubit
• Quantum-state engineering with Josephson-junction devices
• Single-shot measurement of the Josephson charge qubit
• Rabi oscillations, Ramsey fringes and spin echoes in an electrical circuit

Cited by

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