Abstract
We propose a tunable macroscopic quantum system based on two fractional vortices. Our analysis shows that two coupled fractional vortices pinned at two artificially created κ discontinuities of the Josephson phase in a long Josephson junction can reach the quantum regime where coherent quantum oscillations arise. For this purpose we map the dynamics of this system to that of a single particle in a double-well potential. By tuning the κ discontinuities with injector currents, we are able to control the parameters of the effective double-well potential as well as to prepare a desired state of the fractional vortex molecule. The values of the parameters derived from this model suggest that an experimental realization of this tunable macroscopic quantum system is possible with today's technology.
Highlights
What experimental evidence do we have that quantum mechanics is valid at the macroscopic level? This question raised [1] in 1980 by A
In the present paper we show that it is possible to tune two fractional Josephson vortices into the quantum regime and obtain in this way a system in which we can observe macroscopic quantum phenomena
We show how our system can be tuned from a classical regime, where no quantum oscillations are observable, into the quantum regime
Summary
What experimental evidence do we have that quantum mechanics is valid at the macroscopic level? This question raised [1] in 1980 by A. J. Leggett has triggered a flood of theoretical work [2, 3, 4] and experiments on a wide variety of quantum systems ranging from photons in cavities [5, 6], ions in traps [7], cold atoms [8] via high-spin molecules [9] to superconducting devices [10]. In the present paper we show that it is possible to tune two fractional Josephson vortices into the quantum regime and obtain in this way a system in which we can observe macroscopic quantum phenomena
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
