Exciton trapping in magnetic wire structures

The lateral magnetic confinement of quasi-two-dimensional excitons into wire-like structures is studied. Spin effects are taken into account and two different magnetic field profiles are considered, which can be created experimentally by the deposition of a ferromagnetic stripe on a semiconductor quantum well with magnetization parallel or perpendicular to the growth direction of the well. We find that it is possible to confine excitons into one-dimensional (1D) traps. We show that the dependence of the confinement energy on the exciton wave vector, which is related to its free direction of motion along the wire direction, is very small. Through the application of a background magnetic field it is possible to move the position of the trapping region towards the edge of the ferromagnetic stripe or even underneath the stripe. The exact position of this 1D exciton channel depends on the strength of the background magnetic field and on the magnetic polarization direction of the ferromagnetic film.