Semiclassical approximation of the magnetic Schrödinger operator on a strip : dynamics and spectrum

In the semiclassical regime (i.e., (cid:15) (cid:38) 0), we study the effect of a slowly varying potential V ((cid:15) t , (cid:15) z ) on the magnetic Schrödinger operator P = D 2 x + ( D z + µ x ) 2 on a strip [− a , a ] × (cid:82) z . The potential V ( t , z ) is assumed to be smooth. We derive the semiclassical dynamics and we describe the asymptotic structure of the spectrum and the resonances of the operator P + V ((cid:15) t , (cid:15) z ) for (cid:15) small enough. All our results depend on the eigenvalues corresponding to D 2 x + (µ x + k ) 2 on L 2 ( [− a , a ] ) with Dirichlet boundary condition. x ≤ a } . The Fourier transfor-mation with respect to z reduces the spectral problem of P to an analysis of the ( k depending) eigenvalues E 0 ( k ), E 1 ( k ), . . . of the Sturm-Liouville operator on the interval [− a , a ] with Dirichlet boundary condition at − a and a .