Low Temperature Properties of the Two-Impurity Kondo Hamiltonian.

For the two-impurity Kondo system, the low-temperature properties -- impurity spin-spin correlation function, susceptibilities, specific heat, and Wilson ratio -- are strongly nonuniversal functions of the ratio (I sub o /T sub K) of the RKKY coupling to the single-impurity Kondo temperature. In particular, there is a new unstable fixed point for an antiferromagnetic coupling with I sub o /T sub K ~ -2.2. We also note a new symmetry -- axial charge -- present even in the one-impurity model.