  We propose a quantum analog of the internal combustion engine used in most
cars. Specifically, we study how to implement the Otto-type quantum heat engine
(QHE) with the assistance of a Maxwell's demon. Three steps are required:
thermalization, quantum measurement, and quantum feedback controlled by the
Maxwell demon. We derive the positive-work condition of this composite QHE. Our
QHE can be constructed using superconducting quantum circuits. We explicitly
demonstrate the essential role of the demon in this macroscopic QHE.
