A ##\Lambda##-enhanced gray molasses cooling

A
Thread starter BillKet
Start date Nov 22, 2023
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Cooling

Nov 22, 2023

BillKet

Hello! I am confused about ##\Lambda##-enhanced gray molasses cooling. I understand that it combines gray molasses cooling with velocity-selective coherent population trapping (VSCPT). But I can't seem to understand what is the difference between these 3 methods. As far as I can tell, the main idea is that, by having 2 laser beams in a Raman setup, one can end up with a dark state, which is a combination of ground state levels, and the likelihood of reaching this dark state increases with reducing the velocity of the atom, hence atoms with low velocities become transparent to the light. But that seems just what VSCPT does. Where is the gray molasses coming into play? @Twigg ? Thank you!

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