New preprint: Landauer’s erasure principle in a squeezed thermal memory

Energy dissipation is a key design factor in digital electronics. Improvements in our understanding of energy dissipation in information-processing devices are of high scientific and technological interest. In 1961, Rolf Landauer argued that there exists a limit to which the power consumption of an erasure operation in a computer memory can be reduced. Fundamental to that principle is the assumption of an operation close to thermal equilibrium. In a new preprint, I show that so-called squeezed thermal states, which may naturally arise in electronic circuits operating in a pulse-driven fashion, can be exploited to reduce the fundamental energy costs of an erasure operation.

PhD position in Experimental Optics/Photonics

Microlaser networks as computational tool

Despite large advances in both algorithms and computer technology, even typical instances of certain computationally hard problems (NP-hard) may be too difficult to be solved on today’s computers. In certain areas of application unconventional computational devices could help to overcome these limitations. In this project, a complex network of microlasers with tune-able tunnel couplings will be developed and tested for its suitability as computational tool in optimization tasks. We aim at demonstrating that the proposed device has the potential to outperform standard methods of solving optimization problems by many orders of magnitude.

For further details see the following announcement. If you are interested in joining our group as a doctorate student, please do not hesitate to contact us (j.klaers ‘at’ We are looking forward to your application.

Update April 2018: the position is filled.

Joined COPS groups @ UTwente

On September 15 2017, I have joined the COPS group at the University of Twente as Assistant Professor for Nanophotonics. At COPS, I will initialize a new experiment based on two-dimensional arrays of coupled microlasers as a computational tool to solve optimization problems.

Beyond the Carnot limit

New publication in Physical Review X:

J. Klaers, S. Faelt, A. Imamoglu, and E. Togan, “Squeezed thermal reservoirs as a resource for a nano-mechanical heat engine beyond the Carnot limit”, Physical Review X 7, 031044 (2017). link

See also the Viewpoint by James Millen.

Coupled photon condensates

New publication in Nature Photonics:

D. Dung, C. Kurtscheid, T. Damm, J. Schmitt, F. Vewinger, M. Weitz, and J. Klaers, “Variable potentials for thermalized light and coupled condensates”, Nature Photonics 11, 565 (2017). link