A nuclear quadrupolar spin quantum heat engine

Abstract

We give an implementable scheme which uses intrinsic quadrupolar nuclear spin interactions to harvest efficient energy from a quantum Otto cycle. We employ realistic parameter regimes for the 23Na nucleus in sodium nitrate. The processes of the cycle are accomplished by orienting the sample with respect to the static magnetic field. The effects of stroke duration on the work output and efficiency are revealed in detail. Finite-time adiabatic transformations leading to quantum friction are found to substantially reduce cycle outputs which are stimulated from the non-secular parts of the quadrupolar interaction. An estimation for the power output at maximum efficiency is also given. We show that with the precise control and manipulation of the intrinsic nuclear spin interactions, for example in an advanced nuclear magnetic resonance setup, makes our scheme implement as a powerful quantum Otto cycle.