This page contains automatically translated content.
Engine from one atom
In its current issue, the science magazine Science reports on a novel heat engine that works with just a single atom. The experiments involved were set up under the direction of Univ. Prof. Dr. Kilian Singer, head of the Department of Experimental Physics I at the University of Kassel, while he was still at Johannes Gutenberg University Mainz (JGU) and were carried out in collaboration with theoretical physicists from the University of Erlangen-Nuremberg.
Since the industrial revolution, heat engines have played a crucial role in our society. They convert thermal energy into mechanical work, such as in vehicles, and have become an indispensable part of our modern lives. At the same time, miniaturization is leading to ever smaller technical devices.
The scientists led by Prof. Dr. Kilian Singer use a so-called Paul trap to store a single, electrically charged calcium atom. The atom can be heated by electrical noise and cooled by laser beams. As a result, it undergoes a thermodynamic cycle comparable to the processes in the cylinder of a classical engine. The generated power is converted into an oscillation of the atom. The atom thus plays the role of both motor and energy storage device.
In extensive series of measurements, the physicists were able to characterize the thermodynamic behavior of the engine. As the researchers now show in their publication, the single-atom motor delivers 10-22 watts of power and has an efficiency of 0.3 percent. Normalizing the power of the single-atom engine to the small mass of an atom, its performance is comparable to that of a car engine. "By reversing the cycle, we can operate the machine as a single-atom refrigerator and use it to cool coupled nanosystems," Johannes Roßnagel, lead author of the study, shares in this regard.
What is particularly important about this research, however, is that the realization of such a nanomotor allows insight into the thermodynamics of individual particles, a highly topical area of research. Future plans include further lowering the working temperature of the machine and studying thermodynamic quantum effects. Theoretical work has suggested increasing the power of a heat engine by coupling it to a quantum bath. This offers a variety of opportunities to go beyond the paradigms of classical thermodynamics and build novel engines.
The project was funded by the German Research Foundation under the project "Single Ion Heat Engine" and by the Volkswagen Foundation under the project "Atomic Nanoassembler".
Publication:
Johannes Roßnagel et al.
A single-atom heat engine
Science, 4/15/2016
DOI: 10.1126/science.aad6320
Images:
http://www.uni-mainz.de/bilder_presse/08_physik_quantum_ein_atom_motor_01.jpg
View of the vacuum chamber with the trap (center). Photo: AG Quantum, JGU Mainz
http://www.uni-mainz.de/bilder_presse/08_physik_quantum_ein_atom_motor_02.jpg
Part of the laser system that alternately cools and heats the atom. Photo: AG Quantum, JGU Mainz
Photoby Prof. Dr. Kilian Singer. Photo: Private
Photoby Johannes Rossnagel. Photo: Private
Further information:
Prof. Dr. Kilian Singer
University of Kassel
Experimental Physics I / Light-Matter Interaction
Phone: +49 561 804-4235
E-mail: ks[at]uni-kassel[dot]de
Further links: