A thermoelectric structure and device including at least first and second material systems having different lattice constants and interposed in contact with each other, and a physical interface at which the at least first and second material systems are joined with a lattice mismatch and at which structural integrity of the first and second material systems is substantially maintained. The at least first and second material systems have a charge carrier transport direction normal to the physical interface and preferably periodically arranged in a superlattice structure.