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Confinement of an alkaline-earth element in a grating magneto-optical trap



Ananya Sitaram, Peter Elgee, Gretchen K. Campbell, Daniel Barker, Nikolai Klimov, Stephen Eckel


We demonstrate a compact magneto-optical trap (MOT) of alkaline-earth atoms using a nanofabricated diffraction grating chip. A single input laser beam, resonant with the broad 1S0 to 1P1 transition of strontium, forms the MOT in combination with three diffracted beams from the grating chip and a magnetic field produced by permanent magnets. A differential pumping tube limits the effect of the heated, effusive source on the background pressure in the trapping region. The system has a total volume of around 2.4 L. With our setup, we have trapped up to 5 x 10^6 88Sr atoms, at a temperature of approximately 6 mK, and with a trap lifetime of approximately 1 s. Our results will aid the effort to miniaturize optical atomic clocks and other quantum technologies based on alkaline-earth atoms.
Physical Review Applied


Laser Cooling, ultracold atoms, atomic clocks


Sitaram, A. , Elgee, P. , Campbell, G. , Barker, D. , Klimov, N. and Eckel, S. (2020), Confinement of an alkaline-earth element in a grating magneto-optical trap, Physical Review Applied (Accessed September 29, 2023)
Created October 14, 2020, Updated October 12, 2021