A milestone for new quantum technologies: Exact simulations of environmental influences on quantum systems

University of Bayreuth, Press Release Nr. 041/2022 - 28 March 2022

Today, quantum systems are becoming increasingly important for technological innovations in information processing, cryptography, photonics, spintronics, and high-performance computing. They are in constant interaction with their environment, which influences their modes of operation in many respects. Physicists at the University of Bayreuth, in cooperation with partners at the Universities of Edinburgh and St. Andrews, have now succeeded in developing a novel algorithm to simulate and calculate these influences. In "Nature Physics" they present their discovery, which is ground-breaking for the understanding of open quantum systems.

The researchers call their algorithm "Automated Compression of Environments (ACE)." "With this development, we have achieved a breakthrough in the simulation of quantum systems. This is because it is of extremely high relevance for high-tech applications of quantum systems to be able to realistically simulate environmental influences. We can expect that our new method will lead to many valuable insights into technologically relevant quantum systems. It will certainly also pave the way for the development of new quantum algorithms and for the control of quantum systems," explains Prof. Dr. Vollrath Martin Axt, who led the research work at the University of Bayreuth.

The new algorithm is characterized by a high degree of flexibility. Unlike many other methods, it is able to describe several different environmental effects together on a microscopic level – and to do so numerically completely, without having to resort to approximations to the model that are common in simulations of many-particle models. The new algorithm also overcomes a number of limitations faced by previous methods for simulating and calculating external influences on quantum systems. "ACE enables a virtually unlimited range of applications: It can be applied equally to bosonic, fermionic, or spin environments. The influences of Gaussian and non-Gaussian environments, linear and non-linear environments, and diagonal and non-diagonal environments can now be simulated equally with high precision," Axt explains.

Quantum technologies in teaching: New funding from the Bavarian Ministry of Science and the Arts

Not only in research, but also in teaching, quantum technology applications and their physical foundations will move more into focus at the University of Bayreuth in the future. As the Bavarian State Ministry of Science and the Arts announced a few days ago, the Faculty of Mathematics, Physics & Computer Science will receive funding of  € 144,000 from High-Tech Agenda Bavaria to expand and intensify teaching in the field of quantum technologies. Equal amounts of funding will go to the universities in Augsburg, Erlangen-Nuremberg, Munich, Regensburg, and Würzburg.

"Investing money in research and technology is one thing, fostering talent is another. We bring the two together: Attracting the bright minds at Bavaria's universities to quantum research and quickly making them fit for the future," explained Science Minister Markus Blume. "We are very pleased about the decision of the Bavarian Ministry of Science. It is an important step in further strengthening quantum physics in Bavaria. In Bayreuth, we will use the funding in particular to set up modern practical experiments that will allow students to independently perform experiments in current research. These experiments are directly related to innovative concepts that form the basis of quantum technologies," says Prof. Dr. Vollrath Martin Axt, Managing Director of the Department of Physics at the University of Bayreuth.

Publication:

• Cygorek, M., Cosacchi, M., Vagov, A. et al.
  Simulation of open quantum systems by automated compression of arbitrary environments
  Nature Physics (2022)
  https://doi.org/10.1038/s41567-022-01544-9
  

Prof. Dr. Vollrath Martin Axt
Chair of Theoretical Physics III - Quantum Theory of Condensed Matter

Universitätsstraße 30, NW II
95447 Bayreuth

E-mail: martin.axt@uni-bayreuth.de

Christian Wißler
Deputy Press & PR Manager, Research Communication

Phone: +49 (0)921 / 55-5356
E-mail: christian.wissler@uni-bayreuth.de