Quantum Particles Form Droplets

Quantum droplets may preserve their form in absence of external confinement because of quantum effects. IQOQI/Harald Ritsch

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the fascinating experiment. In the laboratory, her team observed how macrodroplets formed in a quantum gas. The scientists were surprised to find that the quantum droplets were held together almost without external intervention and solely by quantum effects.

This discovery by the research team in Innsbruck, and a similar work carried out simultaneously by a research group from the University of Stuttgart working with the magnetic element dysprosium, opens up a completely new research area in the field of ultracold quantum gases.

In their experiment the researchers produced a Bose-Einstein condensate of erbium atoms at extremely low temperatures in a vacuum chamber. They then controlled the particle interaction by using an external magnetic field.

The unique properties of magnetic atoms permitted to suppress regular interactions up to a degree that quantum correlations became the driving force. With her team Ferlaino has been able to prove that quantum fluctuations leads to an effective repulsion of particles that provides the necessary surface tension to stabilize a quantum droplet against collapse.

“In our experiment we have, for the first time, realized a controlled crossover from a Bose-Einstein condensate, which behaves like a superfluid gas, into a single giant liquid-like quantum droplet of 20,000 atoms,” explains experimental physicist and first author of the study Lauriane Chomaz.

Thanks to exquisite control of the interatomic interactions in the experiment, the physicists were able to conclusively prove the importance of quantum fluctuations by comparing their experimental data with the theory developed by Luis Santos’s research group at the University of Hanover.

The excellent agreement between theory and experiment unveiled the role of quantum fluctuations together with the counter-intuitive properties of this new phase of matter, which can be found between gaseous Bose-Einstein condensates and liquid superfluid helium. Further investigations of this droplet state may contribute to increasing our knowledge of superfluidity.

Alongside helium, a quantum droplet is the only liquid-type superfluid system known. Ultracold quantum gases offer a unique and perfect platform to study this phenomena because of their high purity and tunability. In the long term, this phase of matter could lead to new insights relevant for studies of supersolidity, which is superfluid condensed matter.

Francesca Ferlaino is Professor at the Institute for Experimental Physics at the University of Innsbruck and Scientific Director at the Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences. The experiment was carried out in close cooperation with a team of theoretical physicists headed by Luis Santos of the University of Hannover. It was supported by the German Research Foundation (DFG) among others.

Publication: Quantum-fluctuation-driven crossover from a dilute Bose-Einstein condensate to a macrodroplet in a dipolar quantum fluid. L. Chomaz, S. Baier, D. Petter, M. J. Mark, F. Wächtler, L. Santos, and F. Ferlaino. Phys. Rev. X 6, 041039
http://dx.doi.org/10.1103/PhysRevX.6.041039

Contacts:
Francesca Ferlaino
Institute of Quantum Optics and Quantum Information
Austrian Academy of Sciences
phone: +43 512 507 52440
email: francesca.ferlaino@uibk.ac.at
web: http://www.erbium.at/

Christian Flatz
Public Relations
Phone: +43 676 872532022
Email: pr-iqoqi@oeaw.ac.at

http://dx.doi.org/10.1103/PhysRevX.6.041039 – Quantum-fluctuation-driven crossover from a dilute Bose-Einstein condensate to a macrodroplet in a dipolar quantum fluid. L. Chomaz, S. Baier, D. Petter, M. J. Mark, F. Wächtler, L. Santos, and F. Ferlaino. Phys. Rev. X 6, 041039
http://www.erbium.at – Dipolar Quantum Gas Group
http://iqoqi.at – Institute of Quantum Optics and Quantum Information (IQOQI)

Media Contact

Dr. Christian Flatz Universität Innsbruck

All latest news from the category: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Back to home

Comments (0)

Write a comment

Newest articles

New way to reduce progression of diabetic kidney disease discovered

Study could help the 4.8 million people in the UK with diabetes. A new way to reduce progression of diabetic kidney disease, affecting 40% of people with diabetes, has been…

Antarctica’s ocean brightens clouds

Gases from phytoplankton in the ocean help form dense clouds that reflect sunlight. The teeming life in the Southern Ocean, which encircles Antarctica, contributes to brightening the clouds that form…

Penguin physics…

… understanding the mechanisms of underwater turning maneuvers in penguins. Penguins constitute a fascinating family of flightless birds that, although somewhat clumsy on land, are extremely talented swimmers. Their incredible…

Partners & Sponsors