a recent report on neweelectronics.co.uk explores the work being done by the u.k. national quantum technology hub in sensors and metrology in the study of cold atoms, in which atoms are cooled to nearly absolute zero through optical molasses or laser cooling.
u.k. researchers are using laser cooling for the study of cold atoms. (wikimedia commons)
cold atoms enable scientists to have increased control to study their internal states. in order to cool the atoms, scientists put the atoms in a field of laser beams tuned to slightly less than the atom’s resonant frequency to cause what is known as optical molasses.
the lasers cause phonons to move into the atoms, but having enough lasers focused on the atom cluster with shifting frequencies will slow the atoms and keep the scatter to a minimum. this process was developed 30 years ago and scientists have been stretching the cooling limits ever since, including a nobel prize-winning study of the heisenberg uncertainty limit.
the article noted, “five areas are being explored at the uk national quantum technology hub in sensors and metrology, based at the university of birmingham: clocks; rotation sensors; magnetic sensors; gravity sensors; and quantum imaging. according to the hub, its strategy is to develop practical prototypes and demonstrators for each sensor technology. the university’s lead industrial partner is teledyne e2v, which has invested ‘several million’ in the projects.”
it added, “all five areas are underpinned by cooling atoms. once that is done, tailored laser or microwave pulses are used to create superposition states, which are recombined after some measurement time to create interference. by using different pulses, laser geometries and traps, different measurements can be made. for example, by separating the paths vertically, or so they enclose an area, allows gravity and rotation to be measured respectively. superposing different energy states allows magnetic fields or time to be determined.”
read more about the work being done at the u.k. national quantum technology hub at http://www.newelectronics.co.uk/electronics-technology/cooling-atoms-to-almost-absolute-zero/154182.
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