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The skutterudite/electrode thermoelectric joints were fabricated with the insertion of Ti foil by spark plasma sintering. The interfacial microstructure and reliability of joints were studied during thermal duration test. A multilayer structure, which was composed of intermetallic compounds, was observed at the CoSb 3 /Ti interface after thermal aging of 20 days. The interfacial reactions and diffusion path between CoSb 3 and Ti were discussed. The contact resistance of CoSb 3 /electrode junction was measured through four-probe method and the thermal contact resistance was calculated based on multilayer mode measurement. Effects of the contact resistivity on the performance of CoSb 3 -based device were discussed.

Stimulated adiabatic passage utilizes radiation pulses to efficiently and selectively transfer population between quantum states, via an intermediate state that is normally decaying. In this Letter, we propose the analog of stimulated adiabatic passage in an acoustic system. It is realized with cavities that correlate through adiabatically time-varying couplings, where the cavities and time-varying couplings mimic discrete states and radiation pulses, respectively. With appropriate arrangements of coupling actions, an acoustic wave can be efficiently transferred from the initial excited cavity to the target cavity in the forward direction, immune to the intermediate dark cavity. On the other hand, for the backward propagation, the acoustic energy is perfectly localized in the intermediate dark cavity and completely dissipated. We analytically, numerically, and experimentally demonstrate such unidirectional sound localization and unveil the essential role of zero-eigenvalue eigenstates in the adiabatic passage process.