Bound states in a two-dimensional short range potential induced by the spin-orbit interaction.

We have discovered an unexpected and surprising fact: a 2D axially symmetric short-range potential contains an infinite number of the levels of negative energy if one takes into account the spin-orbit (SO) interaction. For a shallow well (meU0R2/h2<<1, where me is the effective mass and U0 and R are the depth and the radius of the well, respectively) and weak SO coupling (/alpha/meR/h<<1, where alpha is the SO coupling constant) exactly one twofold degenerate bound state exists for each value of the half-integer moment j=m+1/2, and the corresponding binding energy Em extremely rapidly decreases with increasing m.