I saw a fantastic program on the TV last night with a use of lasers that I never knew existed. Everyone knows that lasers can be used to heat things up, but to cool things down to a fraction of a degree above absolute zero???
They are used to create a new state of matter called a Bose-Einstein condensate, which can only exist at fractions of a degree above absolute zero (-273 degrees C)
A target cloud of atoms are contained in a vacuum , now these atoms vibrate at a known frequency, a laser is then fired at this cloud of atoms at exactly the same frequency, but at a different phase, they effectively absorb this out of phase laser light and so the vibration cancels itself out, stopping the atoms vibrating , and effectively cooling themselves to just above absolute zero.
At these Temperatures, a new state of matter can exist called a Bose-Einstein Condensate (quantum state of matter and difficult to explain). If a new laser beam is fired into this new state of matter it will slow the laser beam down from 186, 000 miles per second (speed of light in a vacuum) to just 20mph in the condensate
When the laser beam exits the other side of the condensate it speeds back up to its usual 186, 000 miles per second.
Now that is crazy laser science.
Jase
They are used to create a new state of matter called a Bose-Einstein condensate, which can only exist at fractions of a degree above absolute zero (-273 degrees C)
A target cloud of atoms are contained in a vacuum , now these atoms vibrate at a known frequency, a laser is then fired at this cloud of atoms at exactly the same frequency, but at a different phase, they effectively absorb this out of phase laser light and so the vibration cancels itself out, stopping the atoms vibrating , and effectively cooling themselves to just above absolute zero.
At these Temperatures, a new state of matter can exist called a Bose-Einstein Condensate (quantum state of matter and difficult to explain). If a new laser beam is fired into this new state of matter it will slow the laser beam down from 186, 000 miles per second (speed of light in a vacuum) to just 20mph in the condensate
When the laser beam exits the other side of the condensate it speeds back up to its usual 186, 000 miles per second.
Now that is crazy laser science.
Jase