Quantum Heat Machines with Trapped Ions

Quantum heat machines (QHM) are those quantum systems that convert heat into the useful form of work. Specific kinds of QHMs, namely the heat engines and the refrigerators, among others have been studied in quantum regimes, using discrete strokes or continuous strokes. Heat engines take the heat from a hot bath, deliver a certain amount of work, and release heat to the cold bath. In most of the proposals of QHMs it is assumed that the hot bath and the cold bath are physically separated and can be switched on or off in a controlled way, just as in the case of their classical counterpart. In quantum regime, however, the interaction between the system and the bath is never switched off. Therefore, newer strategies are required for a QHM that can be implemented in a realistic scenario, and also within the quantum framework. Here, we show how one can implement different strokes of an Otto engine, using a single trapped ion. Using two ions, one can even build a refrigerator. Further, we study how a QHM performs across the critical value of an external parameter, pertaining to the quantum phase transition

Reference
1. S. Chand and A. Biswas, Europhys. Lett., 118, 6 (2017).
2. S. Chand and A. Biswas, Phys. Rev. E, 95, 032111 (2017).