Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bon MOT: Innovative atom trap catches highly magnetic atoms

04.04.2008
A research team from the National Institute of Standards and Technology (NIST) and the University of Maryland has succeeded in cooling atoms of a rare-earth element, erbium, to within two millionths of a degree of absolute zero using a novel trapping and laser cooling technique.

Their recent report* is a major step towards a capability to capture, cool and manipulate individual atoms of erbium, an element with unique optical properties that promises highly sensitive nanoscale force or magnetic sensors, as well as single-photon sources and amplifiers at telecommunications wavelengths. It also may have applications in quantum computing devices.

The strongly counterintuitive technique of “laser cooling” to slow down atoms to very low speeds—temperatures close to absolute zero—has become a platform technology of atomic physics. Laser cooling combined with specially arranged magnetic fields—a so-called magneto-optical trap (MOT)—has enabled the creation of Bose-Einstein condensates, the capture of neutral atoms for experiments in quantum computing and ultra-precise time-keeping and spectroscopy experiments. The technique originally focused on atoms that were only weakly magnetic and had relatively simple energy structures that could be exploited for cooling, but two years ago a NIST team showed that the far more complex energy structures of erbium, a strongly magnetic element, also could be manipulated for laser cooling.

The typical MOT uses a combination of six tuned laser beams converging on a point that is in a low magnetic field but surrounded by stronger fields. Originally, the lasers were tuned near a strong natural energy oscillation or resonance in the atom, a condition that provides efficient cooling but to only moderately low temperatures. In the new work, the research team instead used much gentler forces applied through a very weak resonance in order to bring erbium atoms to within a few millionths of a degree of absolute zero. Such weak resonances are only available in atoms with complex energy structures, and previously have been used only with a select group of non-magnetic atoms. When a strongly magnetic atom like erbium is used, the combination of strong magnetic forces and weak absorption of laser photons makes a traditional MOT unstable.

To beat this, the NIST/UM team turned classic MOT principles on their heads. Rather than shifting the laser frequency towards the red end of the spectrum—to impact fast, high-temperature atoms more than slow, cold ones—they shifted the laser towards the blue side to take advantage of the effects of the magnetic field on the highly magnetic erbium. Magnetism holds the atoms stably trapped while the lasers gently pushed them against the field, all the while extracting energy and cooling them. The delicate balancing act not only cools and traps the elusive erbium atoms, it does it more efficiently. The team’s modified trap design uses only a single laser and can cool erbium atoms to within two millionths of a degree of absolute zero. By contrast, a conventional MOT only brings rubidium atoms to about one ten-thousandth of a degree.

Erbium commonly is used in optical communications components for its convenient magneto-optical properties. The new trapping technique raises the possibility of using erbium and similar lanthanide elements for unique nanoscale magnetic field detectors, atomic resolution metrology, optical computing systems and quantum computing.

Michael Baum | EurekAlert!
Further information:
http://www.nist.gov

More articles from Physics and Astronomy:

nachricht Appreciating the classical elegance of time crystals
20.09.2019 | ETH Zurich Department of Physics

nachricht 'Nanochains' could increase battery capacity, cut charging time
20.09.2019 | Purdue University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: 'Nanochains' could increase battery capacity, cut charging time

How long the battery of your phone or computer lasts depends on how many lithium ions can be stored in the battery's negative electrode material. If the battery runs out of these ions, it can't generate an electrical current to run a device and ultimately fails.

Materials with a higher lithium ion storage capacity are either too heavy or the wrong shape to replace graphite, the electrode material currently used in...

Im Focus: Stevens team closes in on 'holy grail' of room temperature quantum computing chips

Photons interact on chip-based system with unprecedented efficiency

To process information, photons must interact. However, these tiny packets of light want nothing to do with each other, each passing by without altering the...

Im Focus: Happy hour for time-resolved crystallography

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.

The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.

Im Focus: Modular OLED light strips

At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.

Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...

Im Focus: Tomorrow´s coolants of choice

Scientists assess the potential of magnetic-cooling materials

Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

 
Latest News

Wire laser material deposition – a smart way to save costs

24.09.2019 | Trade Fair News

On the trail of self-healing processes: Bayreuth biochemists reveal insights into extraordinary regenerative ability

23.09.2019 | Life Sciences

New method for the measurement of nano-structured light fields

23.09.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>