| How is BEC made? The Introduction It took 70 years to realize Einstein's concept of Bose-Einstein condensation
    in a gas.  It was first accomplished by Eric Cornell and Carl Wieman in
    Boulder, Colorado in 1995.  They did it by cooling atoms to a much lower
    temperature than had been previously achieved. Their technique used laser
    light to first cool and hold the atoms, and then these atoms were further
    cooled by something called evaporative cooling. 
 
       
 
     It looks like a pretty simple piece of equipment for such an important
    experiment.  Is that really all there was? 
 
     Not exactly.  There is a table full of equipment associated with the lasers,
    and they needed to produce exactly the right color of light.  Also there is a
    computer and a bunch of other electronic equipment for controlling everything
    and making measurements. Still, it was a pretty simple and inexpensive
    apparatus compared to many physics experiments today.  It only cost about
    $50,000-100,000 for the equipment, but that does not include a lot of hard
    work that went into putting it all together! 
 
     So how cold do the atoms have to be to reach BEC? 
 
     Less than one millionth of a degree above Absolute Zero, which is millions of
    times colder than the lowest temperature found in the depths of outer space.
    (Click here for more information about
    Temperature) 
 
     That sounds pretty cold.  How do they do it? 
 
     Well it takes two stages.  Sort of like taking a pan out of a hot oven and
    letting it cool off in air first, and then dunking it in ice water.  Except
    the first step here is to shine laser light on the atoms to cool them to about
    1/10,000 of a degree above Absolute zero, and the second step is to
    evaporatively cool them further. 
 
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