Measurement-induced operation of two-ion quantum heat machines

摘要

We show how one can implement a quantum heat machine by using two interacting trapped ions, in presenceof a thermal bath. The electronic states of the ions act like a working substance, while the vibrational mode ismodelled as the cold bath. The heat exchange with the cold bath is mimicked by the projective measurementof the electronic states. We show how such measurement in a suitable basis can lead to either a quantum heatengine or a refrigerator, which undergoes a quantum Otto cycle. The local magnetic field is adiabatically changedduring the heat cycle. The performance of the heat machine depends upon the interaction strength between theions, the magnetic fields, and the measurement cost. In our model, the coupling to the hot and the cold bathsis never switched off in an alternative fashion during the heat cycle, unlike other existing proposals of quantumheat engines. This makes our proposal experimentally realizable using current tapped-ion technology.