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Bose-Einstein condensate

A Bose–Einstein condensate (BEC) is a state of matter of a dilute gas of weakly interacting bosons confined in an external potential and cooled to temperatures very near absolute zero (0 K or −273.15 °C). Under such conditions, a large fraction of the bosons occupy the lowest quantum state of the external potential, at which point quantum effects become apparent on a macroscopic scale.

This state of matter was first predicted by Satyendra Nath Bose and Albert Einstein in 1924–25. Bose first sent a paper to Einstein on the quantum statistics of light quanta (now called photons). Einstein was impressed, translated the paper himself from English to German and submitted it for Bose to the Zeitschrift für Physik, which published it. Einstein then extended Bose's ideas to material particles (or matter) in two other papers.

Seventy years later, the first gaseous condensate was produced by Eric Cornell and Carl Wieman in 1995 at the University of Colorado at Boulder NIST-JILA lab, using a gas of rubidium atoms cooled to 170 nanokelvin (nK) (1.7×10−7 K). For their achievements Cornell, Wieman, and Wolfgang Ketterle at MIT received the 2001 Nobel Prize in Physics. In November 2010 the first photon BEC was observed.

The slowing of atoms by the use of cooling apparatus produced a singular quantum state known as a Bose condensate or Bose–Einstein condensate. This phenomenon was predicted in 1925 by generalizing Satyendra Nath Bose's work on the statistical mechanics of (massless) photons to (massive) atoms. (The Einstein manuscript, once believed to be lost, was found in a library at Leiden University in 2005.) The result of the efforts of Bose and Einstein is the concept of a Bose gas, governed by Bose–Einstein statistics, which describes the statistical distribution of identical particles with integer spin, now known as bosons. Bosonic particles, which include the photon as well as atoms such as helium-4, are allowed to share quantum states with each other. Einstein demonstrated that cooling bosonic atoms to a very low temperature would cause them to fall (or "condense") into the lowest accessible quantum state, resulting in a new form of matter. Wikipedia
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'Quantum particles can be divided into two types: fermions and bosons. When cooled down to near-absolute zero temperatures, bosons can condense together into a collective state of matter called a Bose-Einstein condensate where they occupy the same quantum state (e.g. same place and velocity simultaneously). This state of matter allows us to observe remarkable phenomena such as superconductivity – the ability to conduct electric energy with zero resistance. One of the greatest challenges in physics has been to realistically create a Bose-Einstein condensate using photon|, which would have significant applications in laser and even solar panel technology.'" http://phys.org/news/2014-03-capturing-condensing-realistic-conditions.html#jCp

See Also

Bjerknes Effect
Coupling
Law of Attraction
Law of Harmony

Page last modified on Monday 24 of March, 2014 13:05:10 MDT

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