  Jerky elasticity was observed by dynamical mechanical analyzer measurements
in a single crystal of the shape memory alloy Cu74.08Al23.13Be2.79. Jerks
appear as spikes in the dissipation of the elastic response function and relate
to the formation of avalanches during the transformation between the austenite
and the martensite phase. The statistics of the avalanches follows the
predictions of avalanche criticality P(E) proportional to E-epsilon where P(E)
is the probability of finding an avalanche with the energy E. This result
reproduces, within experimental uncertainties, previous findings by acoustic
emission techniques.
