  The electronic structure of the semiconductor double concentric quantum
nano-ring (DCQR) is studied under the single sub-band effective mass approach.
We show that in the weakly coupled DCQR, that has been placed in transverse
magnetic field, the electron spatial transition between the rings can occur due
to electron level anti-crossing. The anti-crossing of the levels with different
radial quantum numbers provides the conditions when the electron tunneling
between rings becomes possible. Results of numerical simulation for the
electron transition are presented for DCQRs of different geometry. In
particularly, the system of a QR with a QD located at center of this QR is
considered.
