  Quantum tunneling between two potential wells in a magnetic field can be
strongly increased when the potential barrier varies in the direction
perpendicular to the line connecting the two wells and remains constant along
this line. An oscillatory structure of the wave function is formed in the
direction joining the wells. The resulting motion can be coherent like motion
in a conventional narrow band periodic structure. A particle penetrates the
barrier over a long distance which strongly contrasts to WKB-like tunneling.
The whole problem is stationary. A not very small tunneling transparency can be
set between two quantum wires with real physical parameters and separated by a
long potential barrier. The phenomenon is connected to Euclidean resonance.
