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تسجيل مستخدم جديدAn optical clock with neutral atoms confined in a shallow trap
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تأليف
Pierre Lemonde
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We study the trap depth requirement for the realization of an optical clock using atoms confined in a lattice. We show that site-to-site tunnelling leads to a residual sensitivity to the atom dynamics hence requiring large depths (50 to $100 E_r$ for Sr) to avoid any frequency shift or line broadening of the atomic transition at the $10^{-17}-10^{-18}$ level. Such large depths and the corresponding laser power may, however, lead to difficulties (e.g. higher order light shifts, two-photon ionization, technical difficulties) and therefore one would like to operate the clock in much shallower traps. To circumvent this problem we propose the use of an accelerated lattice. Acceleration lifts the degeneracy between adjacents potential wells which strongly inhibits tunnelling. We show that using the Earths gravity, much shallower traps (down to $5 E_r$ for Sr) can be used for the same accuracy goal.
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We report the first accuracy evaluation of an optical lattice clock based on the 1S0 - 3P0 transition of an alkaline earth boson, namely 88Sr atoms. This transition has been enabled using a static coupling magnetic field. The clock frequency is deter
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We have examined loading of 85Rb atoms into a shallow Far-Off-Resonance Trap (FORT) from an optical molasses and compared it to loading from a Magneto-Optical Trap (MOT). We found that substantially more atoms could be loaded into the FORT via an opt
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