Detection of a Schroedinger's Cat State in an rf-SQUID

Details Detection of a Schroedinger's Cat State in an rf-SQUID Detection of a Schroedinger's Cat State in an rf-SQUID

2000-04-18

arxiv.org/abs/cond-mat/0004293v2

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

3 RevTeX pages, 4 postscript figures, one in color. Submitted to Nature. Fig. 1 replaced (Postscript problem fixed)

Scientific paper

We present experimental evidence for a coherent superposition of macroscopically distinct flux states in an rf-SQUID. When the external flux Phi_x applied to the SQUID is near 1/2 of a flux quantum Phi_0, the SQUID has two nearly degenerate configurations: the zero- and one-fluxoid states, corresponding to a few microamperes of current flowing clockwise or counterclockwise, respectively. The system is modeled as a particle in a double-well potential where each well represents a distinct fluxoid state (0 or 1) and the barrier between the wells can be controlled in situ. For low damping and a sufficiently high barrier, the system has a set of quantized energy levels localized in each well. The relative energies of these levels can be varied with Phi_x. External microwaves are used to pump the system from the well-localized ground state of one well into one of a pair of excited states nearer the top of the barrier. We spectroscopically map out the energy of these levels in the neighborhood of their degeneracy point by varying Phi_x as well as the barrier height. We find a splitting between the two states at this point, when both states are below the classical energy barrier, indicating that the system attains a coherent superposition of flux basis states that are macroscopically distinct in that their mean fluxes differ by more than 1/4 Phi_0 and their currents differ by several microamperes.

Affiliated with

Also associated with

No associations

Rating

Detection of a Schroedinger's Cat State in an rf-SQUID does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Detection of a Schroedinger's Cat State in an rf-SQUID, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Detection of a Schroedinger's Cat State in an rf-SQUID will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-6684