Ultrasonic attenuation due to hopping of silver ions in superionic conductors

The conductivity and ultrasonic absorption in superionic conductors are condsidered. The hopping motion of silver ions exhibit collective properties because of the Fermi type site occupation numbers. The calculated a.c. conductivity is different from the ordinary Drude expression. The ultrasonic wave modulate the hopping motion of the silver ions and produce space charge. The dissipation of the wave energy is due to this production and is calculated as Joule heating. The absorption coefficient is proportional to the conductivity and the square power of the frequency in agreement with the experimental results.