Phys. Rev. B 55, No. 8, 5214-5219 (1997)
Full text: PDF
The problem of a bound state of two particles confined to parallel two-dimensional layers and interacting via dipole-dipole or dipole-charge laws arises in connection with the study of bound states of charge-transfer excitons at parallel interfaces or biexcitons and charged exciton complexes in double quantum wells. Binding energies of the dipole-charge and the dipole-dipole complexes are calculated as functions of the corresponding coupling constants. It is shown that for the dipole-charge interaction the bound state exists at an arbitrary small coupling constant, though the binding energy decreases dramatically when the coupling constant falls below some critical value. On the contrary, it is shown for the dipole-dipole interaction that the bound state exists only when the coupling constant exceeds a critical value.
©1997 The American Physical Society