Featured Research

from universities, journals, and other organizations

First Bose-Einstein Condensate With Calcium Atoms Produced

Date:
September 24, 2009
Source:
Physikalisch-Technische Bundesanstalt (PTB)
Summary:
Physicists in Germany have succeeded for the first time worldwide in producing a Bose-Einstein condensate from the alkaline earth element calcium. The use of alkaline earth atoms creates new potential for precision measurements -- for example, for the determination of gravitational fields.

Like a giant wave in the midst of a sea of gaseous calcium atoms, the Bose-Einstein condensate soars. It is composed of approx. 20 000 atoms which are normally not visible to the human eye. However the waves which describe the atoms quantum mechanically, all oscillate synchronously in the condensate and accumulate to form a dense giant wave. In this way, the microscopic pile-up of atoms suddenly becomes macroscopic and therefore visible.
Credit: Image courtesy of Physikalisch-Technische Bundesanstalt (PTB)

The physicist and Nobel Prize winner Wolfgang Ketterle once described it as an "identity crisis" of atoms: If atoms are caught in a trap and cooled to a temperature close to the absolute zero point, they condense – similar to vapour condensing to water – and take on an all new condition: They become indistinguishable. This collective condition is called – named for its intellectual fathers – Bose-Einstein condensate.

Related Articles


Physicists at the Physikalisch-Technische Bundesanstalt (PTB) have now succeeded for the first time worldwide in producing a Bose-Einstein condensate from the alkaline earth element calcium. The use of alkaline earth atoms creates new potential for precision measurements -- for example, for the determination of gravitational fields. Because as opposed to previous Bose-Einstein condensates from alkali atoms, alkaline earth metals react one million times more responsively to the wavelength at optical excitations – a fact which can be used for super exact measurements. Theresults have now been published in Physical Review Letters.

Quantum mechanical background

Atoms in gases at room temperature behave like a wild bunch: They fly pell-mell at different speeds, collide with one another, and are then hurled again in another direction. However at extremely low temperatures close to the absolute zero point at zero Kelvin (–273.15 degrees Celsius) they nearly come to a standstill. At this point, the laws of quantum mechanics come into effect; these cannot be observed in everyday life and have an unsettling effect on many a non-physicist. The idea of atoms as small spheres does not work any longer. In fact, atoms can now only be described quantum mechanically by waves. Like water waves they can overlap each other. In the case of a Bose-Einstein condensate, the wave functions of up to one million atoms are so synchronised that they pile up to form a giant wave. These formations can grow to one millimeter in size and they can then be photographed. The microcosm presents itself macroscopically – it becomes visible for the observer. In the past few years, such Bose-Einstein condensates have been used for diverse investigations on the fundamentals of quantum mechanics, as a model system for solids or in quantum information.

Potential applications

The wave patterns of excited Bose-Einstein condensates are very responsive to their environment. Thus, by investigating these patterns it is possible to produce highly responsive interferometric sensors, e.g. for magnetic fields but also for gravitation. For the manipulation und excitation of condensates light is used. All Bose-Einstein condensates produced so far worldwide have a common disadvantage: Their broad optical transitions do not allow any precision excitations. In the case of Bose-Einstein condensates from alkaline earth atoms (e.g. calcium and strontium, both of which are being investigated at PTB as to their suitability as optical clocks) their super-narrow optical transitions offer novel potential for precision investigations. Conceivable is their use on satellites, e.g. by geophysicists, who study the deformation of the Earth and thus the change in gravitation.

Method

At PTB it was possible for the first time worldwide to produce a Bose-Einstein condensate from alkaline earth atoms. To this end, 2ˇ106 calcium atoms precooled in a magneto-optical trap were loaded at a temperature of 20ľK into optical forceps. Due to the weakening of the holding force hot atoms vaporize, whereby the remaining atoms are cooled. At a temperature of typically 200 nK the critical temperature is reached with 105 atoms. Of these, approx. 2ˇ104 atoms can be cooled to form a pure condensate.


Story Source:

The above story is based on materials provided by Physikalisch-Technische Bundesanstalt (PTB). Note: Materials may be edited for content and length.


Journal Reference:

  1. Sebastian Kraft, Felix Vogt, Oliver Appel, Fritz Riehle, and Uwe Sterr. Bose-Einstein Condensation of Alkaline Earth Atoms: 40Ca. Physical Review Letters, 2009; DOI: 10.1103/PhysRevLett.103.130401

Cite This Page:

Physikalisch-Technische Bundesanstalt (PTB). "First Bose-Einstein Condensate With Calcium Atoms Produced." ScienceDaily. ScienceDaily, 24 September 2009. <www.sciencedaily.com/releases/2009/09/090922100141.htm>.
Physikalisch-Technische Bundesanstalt (PTB). (2009, September 24). First Bose-Einstein Condensate With Calcium Atoms Produced. ScienceDaily. Retrieved December 18, 2014 from www.sciencedaily.com/releases/2009/09/090922100141.htm
Physikalisch-Technische Bundesanstalt (PTB). "First Bose-Einstein Condensate With Calcium Atoms Produced." ScienceDaily. www.sciencedaily.com/releases/2009/09/090922100141.htm (accessed December 18, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Thursday, December 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) — The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
3D Printed Cookies Just in Time for Christmas

3D Printed Cookies Just in Time for Christmas

Reuters - Innovations Video Online (Dec. 18, 2014) — A tech company in Spain have combined technology with cuisine to develop the 'Foodini', a 3D printer designed to print the perfect cookie for Santa. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
First Etihad Superjumbo Flight in December

First Etihad Superjumbo Flight in December

AFP (Dec. 18, 2014) — The first flight of Etihad Airways' long-awaited Airbus A380 superjumbo will take place later in December, the Abu Dhabi carrier said Thursday, also announcing its first Boeing 787 Dreamliner route. Duration: 01:09 Video provided by AFP
Powered by NewsLook.com
Ford Expands Air Bag Recall Nationwide

Ford Expands Air Bag Recall Nationwide

Newsy (Dec. 18, 2014) — The automaker added 447,000 vehicles to its recall list, bringing the total to more than 502,000. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins