  The structural relaxation, potential energy states, and mechanical properties
of a model glass subjected to thermal cycling are investigated using molecular
dynamics simulations. We study a non-additive binary mixture which is annealed
with different cooling rates from the liquid phase to a low temperature well
below the glass transition. The thermal treatment is applied by repeatedly
heating and cooling the system at constant pressure, thus temporarily inducing
internal stresses upon thermal expansion. We find that poorly annealed glasses
are relocated to progressively lower levels of potential energy over
consecutive cycles, whereas well annealed glasses can be rejuvenated at
sufficiently large amplitudes of thermal cycling. Moreover, the lowest levels
of potential energy after one hundred cycles are detected at a certain
temperature amplitude for all cooling rates. The structural transition to
different energy states is accompanied by collective nonaffine displacements of
atoms that are organized into clusters, whose typical size becomes larger with
increasing cooling rate or temperature amplitude. We show that the elastic
modulus and the peak value of the stress overshoot exhibit distinct maxima at
the cycling amplitude, which corresponds to the minimum of the potential
energy. The simulation results indicate that the yielding peak as a function of
the cycling amplitude for quickly annealed glasses represents a lower bound for
the maximum stress in glasses prepared with lower cooling rates.
