The exact solution by means of Bethe's Ansatz of a variant of the two-impurity Kondo problem is presented. The occupation of the singlet and triplet states, the expectation value $〈{\overrightarrow{S}}_1̇{\hat{S}}_2〉$, the homogeneous and staggered magnetic field susceptibilities, and the specific heat $\gamma$ coefficient are studied for the ground state as a function of the Ruderman-Kittel-Kasuya-Yosida–coupling strength.

• Received 22 January 1998

DOI:https://doi.org/10.1103/PhysRevLett.80.4975