Researchers from Heidelberg and Vienna demonstrate universal dynamics in clouds of Rubidium atoms
Different physical systems – isolated from the environment and far from equilibrium – can behave the same. Quantum mechanically, this is the case if the dynamics of a many-particle system become universal.
In two fundamentally different experiments, physicists from Heidelberg University and the TU Vienna (Austria) have now succeeded in verifying this universality in ultracold clouds of Rubidium atoms.
The improved understanding of the systems studied permit making predictions for totally different systems. The research results were published in “Nature”.
The expansion of the Universe directly after the Big Bang, the ramifications of a heavy-ion collision in the particle accelerator at CERN, or clouds of atoms at ultracold temperatures – many isolated physical systems are naturally out of equilibrium, yet the relevant quantities are often hard to measure.
This is different for ultracold atomic gases. "The high degree of control over our system allows us to set up interesting initial conditions. In the course of the dynamics we are able to measure precisely the universal observables, for example the state of the atoms, spatially resolved“, explains Prof. Dr Markus Oberthaler, founder of the Synthetic Quantum Systems research group at Heidelberg University’s Kirchhoff Institute for Physics.
In their experiment, the Heidelberg researchers prepared about 70,000 ultracold Rubidium atoms. They were thrown out of equilibrium by a rapid change in an external magnetic field.
At ultracold temperatures around 10 nanokelvins and in perfect isolation from the environment, the atoms behave like magnets that interact with each other. The characteristics of the universal dynamics become observable only after – for experiments with ultracold atoms – long evolution times. “This requires an extremely stable experimental setup, but it does allow us to investigate the dynamics very precisely”, says Maximilian Prüfer, the primary author of the study.
The research group of Prof. Dr Jörg Schmiedmayer at the TU Vienna observed another type of universal dynamics. "Universality provides a new method to gain essential information about quantum systems usually not accessible in the laboratory“, says Jörg Schmiedmayer.
Prof. Dr Thomas Gasenzer of the Kirchhoff Institute for Physics and Prof. Dr Jürgen Berges of the Institute for Theoretical Physics at Ruperto Carola were involved in these investigations. They are also co-authors of the Heidelberg study under the direction of Prof. Oberthaler.
The characterisation of quantum mechanical many-particle systems far from equilibrium is very important, for example, for understanding structure formation in nature. Markus Oberthaler emphasises: “The impressive result of both experiments is that they found two different universality classes. This suggests that we are on the track of a fundamental structure.” The work in Heidelberg and Vienna was conducted under the auspices of the "Isolated quantum systems and universality in extreme conditions" Collaborative Research Centre at Heidelberg University.
Communications and Marketing
Press Office, phone +49 6221 54-2311
Prof. Dr Markus Oberthaler
Kirchhoff Institute for Physics
Phone +49 6221 54-5170
M. Prüfer, P. Kunkel, H. Strobel, S. Lannig, D. Linnemann, C.M. Schmied, J. Berges, T. Gasenzer, and M.K. Oberthaler: Observation of universal dynamics in a spinor Bose gas far from equilibrium. Nature 563, 217-220 (2018), https://doi.org/10.1038/s41586-018-0659-0
S. Erne, R. Bücker, T. Gasenzer, J. Berges, and J. Schmiedmayer: Universal dynamics in an isolated one-dimensional Bose gas far from equilibrium. Nature 563, 225-229 (2018), https://doi.org/10.1038/s41586-018-0667-0
Marietta Fuhrmann-Koch | idw - Informationsdienst Wissenschaft
Intense tests reveal elusive, complex form of common element
09.11.2018 | University of Edinburgh
A Leap Into Quantum Technology
09.11.2018 | Julius-Maximilians-Universität Würzburg
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
Scientists developed specially coated nanometer-sized vehicles that can be actively moved through dense tissue like the vitreous of the eye. So far, the transport of nano-vehicles has only been demonstrated in model systems or biological fluids, but not in real tissue. The work was published in the journal Science Advances and constitutes one step further towards nanorobots becoming minimally-invasive tools for precisely delivering medicine to where it is needed.
Researchers of the “Micro, Nano and Molecular Systems” Lab at the Max Planck Institute for Intelligent Systems in Stuttgart, together with an international...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
09.11.2018 | Earth Sciences
09.11.2018 | Health and Medicine
09.11.2018 | Event News