As the authors report* in an upcoming issue of Physical Review A, the radio-frequency (RF) radiation could serve as a second "knob," in addition to the more traditionally used magnetic fields, for controlling how atoms in an ultracold gas interact.
Just as it is easier to improve reception on a home radio by both electronically tuning the frequency on the receiver and mechanically moving the antenna, having two independent knobs for influencing the interactions in atomic gases could produce richer and more exotic arrangements of ultracold atoms than ever before.
Previous experiments with ultracold gases, including the creation of Bose-Einstein condensates, have controlled atoms by using a single knob—traditionally, magnetic fields. These fields can tune atoms to interact strongly or weakly with their neighbors, pair up into molecules, or even switch the interactions from attractive to repulsive. Adding a second control makes it possible to independently tune the interactions between atoms in different states or even between different types of atoms. Such greater control could lead to even more exotic states of matter. A second knob, for example, may make it easier to create a weird three-atom arrangement known as an Efimov state, whereby two neutral atoms that ordinarily do not interact strongly with one another join together with a third atom under the right conditions.
For many years, researchers had hoped to use RF radiation as a second knob for atoms, but were limited by the high power required. The new work shows that, near magnetic field values that have a big effect on the interactions, significantly less RF power is required, and useful control is possible.
In the new work, the JQI/NIST team examined intriguing experimental data of trapped rubidium atoms taken by the group of David Hall at Amherst College in Massachusetts. This data showed that the RF radiation was an important factor in tuning the atomic collisions. To explain the complicated way in which the collisions varied with RF frequency and magnetic field, NIST theorist Thomas Hanna developed a simple model of the experimental arrangement. The model reconstructed the energy landscape of the rubidium atoms and explained how RF radiation was changing the atoms' interactions with one another. In addition to providing a roadmap for rubidium, this simplified theoretical approach could reveal how to use RF to control ultracold gases consisting of other atomic elements, Hanna says.
* A.M. Kaufman, R.P. Anderson, T.M. Hanna, E. Tiesinga, P.S. Julienne, and D.S. Hall, Radiofrequency dressing of multiple Feshbach resonances, to appear in Physical Review A.
Ben Stein | EurekAlert!
Scientists propose synestia, a new type of planetary object
23.05.2017 | University of California - Davis
Turmoil in sluggish electrons’ existence
23.05.2017 | Max-Planck-Institut für Quantenoptik
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
23.05.2017 | Physics and Astronomy
23.05.2017 | Life Sciences
23.05.2017 | Medical Engineering