quantum entanglement observable at high temperatures

Suppose there is a bulk system at thermodynamic equilibrium. Now push it away from this equilibrium states to non-equilibrium one. Due to the second law of thermodynamics, it is expected this system shall after some time relax to equilibrium eventually. This time is called the relaxation time, which serves a time scale to judge the importance of pure mechanical dynamics. Now if the latter occurs at a much shorter time than the relaxation time, it is hoped that the thermal noises will not take big role, which means the behavior is governed by the pure dynamics. This being so, a system even very high temperatures can show quantum phenomena on the short time scale. This idea was recently written in PRL [Phys. Rev. Lett. 105, 180501 (2010)]. A review is as follows [Nature, 468:769]:

The basic intuition behind this result is as follows. When a system is not in thermal equilibrium, the temperature no longer provides the relevant energy scale against which to compare the system's quantum behaviour. What matters instead is an effective temperature, which can be much lower than the absolute one. This effective temperature is obtained by multiplying the absolute temperature by the rate at which the system approaches equilibrium divided by the driving frequency, the frequency of the signal with which the system is made to oscillate. Galve and colleagues demonstrate that this new condition for entanglement — that the interaction between subsystems should be compared with the thermal energy at the effective temperature — holds quite generally and is intuitively pleasing. It says that if we can drive the system to oscillate within a shorter timescale than the time it takes to reach thermal equilibrium, then an entangled steady state can be attained at higher temperatures than the absolute one.