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تسجيل مستخدم جديدAn ytterbium quantum gas microscope with narrow-line laser cooling
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We demonstrate site-resolved imaging of individual bosonic $^{174}mathrm{Yb}$ atoms in a Hubbard-regime two-dimensional optical lattice with a short lattice constant of 266 nm. To suppress the heating by probe light with the $^1S_0$-$^1P_1$ transition of the wavelength $lambda$ = 399 nm for high-resolution imaging and preserve atoms at the same lattice sites during the fluorescence imaging, we simultaneously cool atoms by additionally applying narrow-line optical molasses with the $^1S_0$-$^3P_1$ transition of the wavelength $lambda$ = 556 nm. We achieve a low temperature of $T = 7.4(1.3) mumathrm{K}$, corresponding to a mean oscillation quantum number along the horizontal axes of 0.22(4) during imaging process. We detect on average 200 fluorescence photons from a single atom within 400 ms exposure time, and estimate the detection fidelity of 87(2)%. The realization of a quantum gas microscope with enough fidelity for Yb atoms in a Hubbard-regime optical lattice opens up the possibilities for studying various kinds of quantum many-body systems such as Bose and Fermi gases, and their mixtures, and also long-range-interacting systems such as Rydberg states.
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