Researchers have created a process that can cool molecules to near absolute zero temperatures through evaporative cooling. Previous processes were then limited to ultra-cooling atoms.
Ultra cold atom physics deals with atoms that are at a temperature close to absolute 0 or 0 K (kelvins). In this field of science, temperature is measured at the nanoscale or at nano-kelvins (nK).
Since it is impossible to bring an object to absolute zero (as stated in the Third Law of Thermodynamics), ultracold atom physics study objects that are close to absolute zero. The coldest an atom has been brought down to is 0.45 nK (nano kelvin) or 4.5 x 10-10 K or 0.00000000045 K.
At these levels, atoms start to behave differently and their properties start to move from classical physics to quantum mechanics.
A property that scientists are interested in is the transformation of atoms into a new form of matter called the Bose-Einstein Condensate (BEC). The Bose-Einstein condensate happens when atoms that are brought down to near absolute zero start to behave like waves rather than particles.
As the temperature goes down, these atoms start to vibrate in the same wavelength. Because of this, they start to behave like a single mass object, the Bose-Einstein condensate.
Laser cooling and evaporative cooling are the two ways that scientists use to lower the temperature of atoms. Laser cooling in simple terms uses laser light on atoms to manipulate photons to lowers the energy level of the atom
With evaporative cooling, atoms with higher energy levels (temperature) are ejected out of an optical or magnetic trap until only atoms with the lowest energy levels are left. BECs and ultracold atoms are at very low temperatures are highly sensitive to heat (2nd Law of Thermodynamics).
Practical applications of ultracold atom physics range from super sensitive sensors to atom chips used in diodes and semiconductors. Current technologies used by magnetic levitation (mag-lev) trains, quantum computers and MRI devices utilize principles behind ultracold atom physics.
Ultra cold atom physics deals with atoms that are at a temperature close to absolute 0 or 0 K (kelvins). In this field of science, temperature is measured at the nanoscale or at nano-kelvins (nK).
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| JILA researchers developed a new magnetic trap and a new technique to achieve "evaporative cooling" of hydroxyl molecules (one hydrogen atom bonded to one oxygen atom). A microwave pulse at a specific frequency converts hot molecules inside the trap to a slightly different energy state. A small electric field is pulsed on briefly to destabilize and eject these converted molecules from the trap. As the microwave frequency is slowly altered, molecules distributed inside the trap (which has a varied magnetic field strength) are progressively converted and removed from the top of the trap, where molecules are hotter, to the bottom, where molecules are cooler. Credit: Baxley and Ye Group/JILA |
At these levels, atoms start to behave differently and their properties start to move from classical physics to quantum mechanics.
A property that scientists are interested in is the transformation of atoms into a new form of matter called the Bose-Einstein Condensate (BEC). The Bose-Einstein condensate happens when atoms that are brought down to near absolute zero start to behave like waves rather than particles.
As the temperature goes down, these atoms start to vibrate in the same wavelength. Because of this, they start to behave like a single mass object, the Bose-Einstein condensate.
Laser cooling and evaporative cooling are the two ways that scientists use to lower the temperature of atoms. Laser cooling in simple terms uses laser light on atoms to manipulate photons to lowers the energy level of the atom
With evaporative cooling, atoms with higher energy levels (temperature) are ejected out of an optical or magnetic trap until only atoms with the lowest energy levels are left. BECs and ultracold atoms are at very low temperatures are highly sensitive to heat (2nd Law of Thermodynamics).
Practical applications of ultracold atom physics range from super sensitive sensors to atom chips used in diodes and semiconductors. Current technologies used by magnetic levitation (mag-lev) trains, quantum computers and MRI devices utilize principles behind ultracold atom physics.
