  We study the effect of the interplay between the Rashba and the Dresselhaus
spin-orbit couplings on the transverse electron focusing in two-dimensional
electron gases. Depending on their relative magnitude, the presence of both
couplings can result in the splitting of the first focusing peak into two or
three. This splitting has information about the relative value of spin-orbit
couplings and therefore about the shape of the Fermi surface. More interesting,
the presence of the third peak is directly related to the tunneling probability
("magnetic breakdown") between orbits corresponding to the different sheets of
the Fermi surface. In addition, destructive interference effects between paths
that involve tunneling and those that do not can be observed in the second
focusing condition. Such electron paths (orbits) could be experimentally
detected using current techniques for imaging the electron flow opening the
possibility to directly observe and characterize the magnetic breakdown effect
in this system.
