ULTRASONIC ATTENUATION AND SOUND VELOCITY ANOMALIES BELOW 5 K IN LaAl2
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چکیده
Anelastic anomalies in LaA12 and (La+O.23at%Gd)Al2 below 10K have been studied by MHz attenuation and sound velocity in the normaland superconducting state. Three anelastic processes involving different lattice defects have been identified. Two of them are shown to exhibit a strong dependence on the concentration of unpaired electrons. For one process this is due to changes in theelectronic component of the resonance damping constant, for the other due to changes of the relaxation rate. The third process is tentatively attributed to trapped hydrogen.
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تاریخ انتشار 2016