Heat engines, such as those found in vehicles, transform thermal energy into mechanical force, and have played an important role in shaping society since the Industrial Revolution. At the same time, progress in miniaturisation is resulting in the creation of ever smaller devices.
A team of researchers led by Professor Kilian Singer, head of the project at Mainz University, used a Paul trap to capture a single electrically charged calcium atom. They then heated the atom with electrically-generated noise and cooled it by using a laser beam. As a result, the atom was subjected to a thermodynamic cycle, meaning the particle moved back and forth within the trap replicating the stroke of a typical engine. The researches claim that the atom not only acts in the same way as an engine but also stores the energy.
The researchers state that their single particle engine can generate power of 10^-22W and operates at 0.3% efficiency. If the power of the single atom engine was scaled up its output would be equivalent to that of a car engine. "By reversing the cycle, we could even use the device as a single atom refrigerator and employ it to cool nano systems coupled to it," explained researcher, Johannes Roßnagel.
However, the researchers say, the principal objective of this research is to provide insight into thermodynamics at the single-particle level. They plan to further lower the operating temperature of the engine in order to investigate thermodynamic quantum effects. In theory, it is assumed that the power of a heat engine can be increased by linking it to a quantum heat bath, providing a wealth of possibilities that can be used to move beyond the standard accepted boundaries of classical thermodynamics and construct new types of engines.
