In an international first, a research team of experimental physicists led by Francesca Ferlaino and theoretical physicists led by Peter Zoller has measured long-range magnetic interactions between ultracold particles confined in an optical lattice. Their work, published in Science, introduces a new control knob to quantum simulation.
Simulations are a popular tool to study physical processes that cannot be investigated experimentally in detail. For example, scientists are challenged to investigate physical processes in materials since their properties are determined by the interactions of single particles, which are hardly measurable directly.
Conventional computers quickly reach their limits when dealing with these complex simulations. At the beginning of the 1980s, Richard Feynman proposed to simulate these processes in a quantum system to overcome this obstacle.
Two decades later, Ignacio Cirac and Peter Zoller presented concrete concepts of how quantum processes could be studied by using ultracold atoms confined in optical lattices. In the last few years, this approach has proven itself in practice and is now broadly applied in experiments.
“We are able to control ultracold particles well in experiments and this has provided us with new insights into physical properties,” says Francesca Ferlaino from the Institute for Experimental Physics of the University of Innsbruck and the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences.
In collaboration with Peter Zoller’s team of theoretical physicists, her research team has now extended this approach for quantum simulations and laid the groundwork for future new research: For the first time, the physicists were able to quantitatively measure long-range interactions between magnetic atoms in optical lattices.
Experimental tool box for matter
Many studies have focused on the investigation of the interaction of short-range particles. “In contrast, we are working with strongly magnetic atoms, which can also interact over long distances,” says co-author Manfred Mark. For their experiment the physicists prepared an ultracold gas of erbium atoms – a Bose-Einstein condensate – in a three dimensional optical lattice of laser beams.
In this simulated solid-body crystal, the particles were arranged similar to eggs in a carton. The distance between the particles was seven times their wave function in the Innsbruck experiment. “By using a magnetic field we are able to directly change the direction of the mini magnets and precisely control how the particles interact – attracting or repelling each other,” explains first author Simon Baier.
A search for exotic quantum phases
“Our collaboration with Zoller, Cai Zi and Mikhail Baranov was indispensable for understanding our measurement results comprehensively,” underlines Francesca Ferlaino. “Our work is another important step towards a better understanding of quantum matter of dipolar atoms because their nature is a lot more complex than the atoms used for ultracold quantum gases in other experiments.”
The research results also lay the groundwork for future studies of novel exotic many-body quantum phases such as checkerboard and stripe phases, which may be created by long-range interactions. “Our study opens the door to finally being able to measure these type of phases,” says Simon Baier, who is already looking into the future. “In principle, we should be able to do this in our experiments as well but we will need to cool the atoms even further from currently 70nK to approximately 2nK.”
The research is supported by the Austrian Science Fund (FWF) and the European Research Council (ERC) among others.
Publication: Extended Bose-Hubbard models with ultracold magnetic atoms. S. Baier, M. J. Mark, D. Petter, K. Aikawa, L. Chomaz, Z. Cai, M. Baranov, P. Zoller, F. Ferlaino. Science 2016
Univ.-Prof. Dr. Francesca Ferlaino
Institute for Experimental Physics
University of Innsbruck
Phone: +43 676 872552440
Dr. Christian Flatz
Public Relations Office
University of Innsbruck
Phone: +43 512 507 32022
Cell: +43 676 872532022
http://www.erbium.at - Dipolar Quantum Gas Group
http://iqoqi.at - Institute of Quantum Optics and Quantum Information
http://www.uibk.ac.at/exphys/ - Department of Experimental Physics, University of Innsbruck
Dr. Christian Flatz | Universität Innsbruck
New quantum liquid crystals may play role in future of computers
21.04.2017 | California Institute of Technology
Light rays from a supernova bent by the curvature of space-time around a galaxy
21.04.2017 | Stockholm University
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...
Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.
A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
21.04.2017 | Physics and Astronomy
21.04.2017 | Health and Medicine
21.04.2017 | Physics and Astronomy