| Autor: |
Frank K. Wilhelm, A.C.J. ter Haar, Terry P. Orlando, J. E. Mooij, Raymond N. Schouten, Seth Lloyd, C.J.P.M. Harmans, Caspar H. van der Wal |
| Rok vydání: |
2001 |
| Předmět: |
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| Zdroj: |
Macroscopic Quantum Coherence and Quantum Computing ISBN: 9781461354598 |
| DOI: |
10.1007/978-1-4615-1245-5_4 |
| Popis: |
We present microwave-spectroscopy experiments on two quantum levels of a superconducting loop with three Josephson junctions. The level separation between the ground state and first excited state shows an anti-crossing where two classical persistent-current states with opposite polarity are degenerate. This is evidence for symmetric and antisymmetric quantum superpositions of two macroscopic states; the classical states have persistent currents of 0.5 µA and correspond to the center-of-mass motion of millions of Cooper pairs. A study of the thermal occupancies of the two quantum levels shows that the loop is at low temperatures in a non-equilibrium state. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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