Jacob Georg, Groot-Berning Karin, Wolf Sebastian, Ulm Stefan, Couturier Luc, Dawkins Samuel T, Poschinger Ulrich G, Schmidt-Kaler Ferdinand, Singer Kilian
QUANTUM, Institut für Physik, Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany.
Institut für Physik, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
Phys Rev Lett. 2016 Jul 22;117(4):043001. doi: 10.1103/PhysRevLett.117.043001. Epub 2016 Jul 20.
We realize a single particle microscope by using deterministically extracted laser-cooled ^{40}Ca^{+} ions from a Paul trap as probe particles for transmission imaging. We demonstrate focusing of the ions to a spot size of 5.8±1.0 nm and a minimum two-sample deviation of the beam position of 1.5 nm in the focal plane. The deterministic source, even when used in combination with an imperfect detector, gives rise to a fivefold increase in the signal-to-noise ratio as compared with conventional Poissonian sources. Gating of the detector signal by the extraction event suppresses dark counts by 6 orders of magnitude. We implement a Bayes experimental design approach to microscopy in order to maximize the gain in spatial information. We demonstrate this method by determining the position of a 1 μm circular hole structure to a precision of 2.7 nm using only 579 probe particles.
我们通过使用从保罗阱中确定性提取的激光冷却的(^{40}Ca^{+})离子作为透射成像的探针粒子，实现了单粒子显微镜。我们展示了离子聚焦到5.8±1.0 nm的光斑尺寸，以及焦平面上光束位置的最小两点偏差为1.5 nm。即使与不完善的探测器结合使用，确定性源与传统泊松源相比，也能使信噪比提高五倍。通过提取事件对探测器信号进行门控，可将暗计数抑制6个数量级。我们在显微镜中实施了贝叶斯实验设计方法，以最大限度地提高空间信息增益。我们仅使用579个探针粒子，就将一个1μm圆形孔结构的位置精确到2.7 nm，证明了这种方法。
