Quantum Superposition of Macroscopic Persistent-Current States

van der Wal, Caspar H.; ter Haar, A.C. J.; Wilhelm, F.K.; Schouten, R.N.; Harmans, C.J. P.M.; Orlando, T.P.; Lloyd, Seth; Mooij, J.E.

doi:10.1126/science.290.5492.773

Quantum Superposition of Macroscopic Persistent-Current States

Oct 27, 2000

Published in:

Science 290 (2000) 5492, 773

Published: Oct 27, 2000

DOI:

10.1126/science.290.5492.773

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Abstract: (American Association for the Advancement of Science)

Microwave spectroscopy experiments have been performed on two quantum levels of a macroscopic superconducting loop with three Josephson junctions. Level repulsion of the ground state and first excited state is found where two classical persistent-current states with opposite polarity are degenerate, indicating symmetric and antisymmetric quantum superpositions of macroscopic states. The two classical states have persistent currents of 0.5 microampere and correspond to the center-of-mass motion of millions of Cooper pairs.

References(38)

Figures(0)

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Quantum Superposition of Macroscopic Persistent-Current States

Citations per year

Quantum mechanics versus macroscopic realism: Is the flux there when nobody looks?

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Quantum superposition of distinct macroscopic states

Wave–particle duality of C60_{60}60​ molecules

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