Precooling Strategy Allows Exponentially Faster Heating

What is the fastest way to heat a system which is coupled to a temperature controlled oven? The intuitive answer is to use only the hottest temperature available. However, we show that often it is possible to achieve an exponentially faster heating protocol. Surprisingly, this protocol can have a precooling stage—cooling the system before heating it shortens the heating time significantly. To demonstrate such improvements in many-body systems, we developed a projection-based method with which such protocols can be found in large systems, as we demonstrate on the 2D antiferromagnet Ising model.