Abstract
We study Cooper-pair tunneling in a voltage-biased superconducting single-electron transistor under microwave irradiation. By tracing the peak positions of a photon-assisted Josephson-quasiparticle current as a function of the microwave frequency, we observe an energy-dispersion curve in the quasicharge space. This shows that energy-level splitting occurs between two macroscopic quantum states of charge coherently superposed by Josephson coupling.
Keywords
PhysicsQuantum tunnellingJosephson effectQuasiparticleCondensed matter physicsMicrowaveCoupling (piping)SuperconductivityPi Josephson junctionAtomic physicsQuantum mechanicsMaterials science
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Publication Info
- Year
- 1997
- Type
- article
- Volume
- 79
- Issue
- 12
- Pages
- 2328-2331
- Citations
- 201
- Access
- Closed
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Cite This
Yasunobu Nakamura,
C. D. Chen,
J. S. Tsai
(1997).
Spectroscopy of Energy-Level Splitting between Two Macroscopic Quantum States of Charge Coherently Superposed by Josephson Coupling.
Physical Review Letters
, 79
(12)
, 2328-2331.
https://doi.org/10.1103/physrevlett.79.2328
Identifiers
- DOI
- 10.1103/physrevlett.79.2328