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تسجيل مستخدم جديدNanosecond super-resolved imaging of a single cold atom by stimulated emission depletion microscopy
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As one of the most critical methods for optical super-resolved microscopy, stimulated emission depletion (STED) microscopy has been widely applied in biological and chemical fields, leading to the Nobel prize of 2014 in chemistry. In cold atomic systems, fast and high-resolution microscopy of individual atoms is crucial since it can provide direct information on the dynamics and correlations of the system. Here, we demonstrate nanosecond two-dimensional snapshots of a single trapped ion beyond the optical diffraction limit, by combining the main idea of STED with the quantum state transition control in cold atoms. We achieve a spatial resolution up to 175 nm and a time resolution up to 50 ns simultaneously using a NA=0.1 objective in the experiment, which is improved over ten times compared to direct fluorescence imaging. To show the potential of this method, we applied it to record the motion of the trapped ion and observe one cycle of the secular motion of the ion with a displacement detection sensitivity of 10 nm. Our method provides a powerful tool for probing particles positions, momenta and correlations, as well as their dynamics in cold atomic systems.
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Nonlinear optical microscopy techniques have emerged as a set of successful tools for biological imaging. Stimulated emission microscopy belongs to a small subset of pump-probe techniques which can image non-fluorescent samples without requiring fluo
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The spatial resolution and fluorescence signal amplitude in stimulated emission depletion (STED) microscopy is limited by the photostability of available fluorophores. Here, we show that negatively-charged silicon vacancy (SiV) centers in diamond are
promising fluorophores for STED microscopy, owing to their photostable, near-infrared emission and favorable photophysical properties. A home-built pulsed STED microscope was used to image shallow implanted SiV centers in bulk diamond at room temperature. The SiV stimulated emission cross section for 765-800 nm light is found to be (4.0 +/- 0.3) x 10^(-17) cm^2, which is approximately 2-4 times larger than that of the negatively-charged diamond nitrogen vacancy center and approaches that of commonly-used organic dye molecules. We performed STED microscopy on isolated SiV centers and observed a lateral full-width-at-half-maximum spot size of 89 +/- 2 nm, limited by the low available STED laser pulse energy (0.4 nJ). For a pulse energy of 5 nJ, the resolution is expected to be ~20 nm. We show that the present microscope can resolve SiV centers separated by <150 nm that cannot be resolved by confocal microscopy.
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Solid state quantum emitters have shown strong potential for applications in quantum information, but spectral inhomogeneity of these emitters poses a significant challenge. We address this issue in a cavity-quantum dot system by demonstrating cavity
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