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Sisyphus Cooling. Justin M. Brown November 8, 2007. Sisyphus Effect. Jean Dalibard and Claude Cohen-Tannoudji (1989) Model to describe sub-Doppler cooling Real atoms have more than two levels. Atoms always travel up a hill to decrease KE. Sub-Doppler Cooling. Doppler Limit
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Sisyphus Cooling Justin M. Brown November 8, 2007
Sisyphus Effect Jean Dalibard and Claude Cohen-Tannoudji (1989) Model to describe sub-Doppler cooling Real atoms have more than two levels Atoms always travel up a hill to decrease KE
Sub-Doppler Cooling Doppler Limit Consider Atomic Zeeman Structure Approach Recoil Limit
Polarization Gradient Counter-propagating perpendicular linear polarizations Polarization Gradient from lightshifts
Limitations • Must Doppler cool first! • Only works over narrow range of velocities • Traveling over multiple potential hills averages out • Doesn’t work if KE > Uhill • Detune laser further and reduce intensity • Cannot break recoil limit – always emit photon
Experimental Implementation 87-Rubidium in an optical dipole trap Circular polarization pumps to end state Miller, K. W., Durr, S, and Weinman, C. Rf-induced Sisyphus cooling in an optical trap. Phys. Rev. A, 66(023406), August 2002.
Experimental Implementation Miller, K. W., Durr, S, and Weinman, C. Rf-induced Sisyphus cooling in an optical trap. Phys. Rev. A, 66(023406), August 2002.