Quantum brachistochrone problem for spin-1 in a magnetic field

Details Quantum brachistochrone problem for spin-1 in a magnetic field Quantum brachistochrone problem for spin-1 in a magnetic field

2007-09-06

arxiv.org/abs/0709.0931v1

Physics

Quantum Physics

7 pages, no figures

Scientific paper

10.1103/PhysRevA.77.014103

We study quantum brachistochrone problem for the spin-1 system in a magnetic field of a constant absolute value. Such system gives us a possibility to examine in detail the statement of papers [A. Carlini {\it et al.}, Phys. Rev. Lett. {\bf 96}, 060503 (2006), D. C. Brody, D. W. Hook, J. Phys. A {\bf 39}, L167, (2006)] that {\it the state vectors realizing the evolution with the minimal time of passage evolve along the subspace spanned by the initial and final state vectors.} Using explicit example we show the existence of quantum brachistochrone with minimal possible time, but the state vector of which, during the evolution {\em leaves} the subspace spanned by the initial and final state vectors. This is the result of the choice of more constrained Hamiltonian then assumed in the general quantum brachistochrone problem, but what is worth noting, despite that such evolution is more complicated it is still time optimal. This might be important for experiment, where general Hamiltonian with the all allowed parameters is difficult to implement, but constrained one depending on magnetic field can be realized. However for pre-constrained Hamiltonian not all final states are accessible. Present result does not contradict general statement of the quantum brachistochrone problem, but gives new insight how time optimal passage can be realized.

Affiliated with

Also associated with

No associations

Rating

Quantum brachistochrone problem for spin-1 in a magnetic field 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 Quantum brachistochrone problem for spin-1 in a magnetic field, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantum brachistochrone problem for spin-1 in a magnetic field will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-658251