An Ultrasonic Study of Trapped Hydrogen Tunneling Systems in Niobium and Tantalum
The properties of trapped hydrogen tunneling systems in Nb and the analogous systems, H in Ta, and D in Nb have been studied with ultrasonic techniques at low temperature. Attenuation due to H in Ta was measured between 0.5 K and 10 K for frequencies between 10 MHz and 55 MHz. The sound velocity change due to H in Nb was measured in both the normal and superconducting state at 10.8 MHz and 33 MHz at temperatures between 0.5 K and 18 K. The attenuation and velocity change due to trapped D in Nb was measured in both the superconducting and normal states for two concentrations of oxygen trapping impurity.
University of Illinois - Urbana-Champaign
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University of Illinois at Urbana-Champaign