Strong Proton-Phonon Coupling in Perovskite-type Electrolyte of Proton-Conducting Fuel Cell

We performed THz spectroscopy of solid electrolytes with controlled water vapor partial pressure and temperature to reveal picosecond proton motions. We also performed the IR reflection spectroscopy, and showed that the protonic motions in protonated BaZrO
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are strongly influenced by lattice vibrations. Such a dynamical long-range proton–lattice correlation will enable new approaches to improve proton conduction in solid-state ionics.