Stimulated emission depletion

Hell, S. W. and Wichmann, J. (1994). Breaking the Diffraction Resolution Limit by Stimulated-Emission—Stimulated-Emission-Depletion Fluorescence Microscopy. Opt. Lett. 19, 780-2. 

Fig. 19.4. Stimulated emission depletion (STED) microscopy reveals densely packed charged nitrogen vacancy (NV) color centers in a diamond crystal, (a) State diagram of NV centers in diamond (see inserted sketch) showing the triplet ground ( A) and fluorescent state ( E) along with a dark singlet state ( E) and the transitions of excitation (Exc), emission (Em), and stimulated emission (STED). (b) The steep decline in fluorescence with increasing intensity /sted shows that the STED-beam is able to switch off the centers almost in a digital-like fashion. This nearly rectangular ...

S.W. HeU, Improvement of lateral resolution in far-Held light microscopy using two-photon excitation with offset beams. Opt. Commun. 106, 19-24 (1994) S.W. HeU, J. Wichmann, Breaking the diffraction resolution limit by stimulated emission stimulated emission depletion fluorescence microscopy. Opt. Lett. 19(11), 780-782 (1994)... 

T.A. Klar et al., Fluorescence microscopy with diffraction resolution limit broken by stimulated emission. Proc. Natl. Acad. Sci. U.S.A 97, 8206-8210 (2000) T.A. Klar, E. Engel, S.W. Hell, Breaking Abbe s diffraction resolution limit in huorescence microscopy with stimulated emission depletion beams of various shapes. Phys. Rev. E 64, 066613, 1-9 (2001)... 

M. Dyba, S. Jakobs, S.W. Hell, Immunohuorescence stimulated emission depletion microscopy. Nat. Biotechnol. 21(11), 1303-1304 (2003)... 

B. Hein, K. WiUig, S.W. HeU, Stimulated emission depletion (STED) nanoscopy of a fluorescent protein - labeled organelle inside a living cell. Proc. Natl. Acad. Sci. USA 105(38), 14271-14276 (2008)... 

Several far-field light microscopy methods have recently been developed to break the diffraction limit. These methods can be largely divided into two categories (1) techniques that employ spatially patterned illumination to sharpen the point-spread function of the microscope, such as stimulated emission depletion (STED) microscopy and related methods using other reversibly saturable optically linear fluorescent transitions (RESOLFT) [1,2], and saturated structured-illumination microscopy (SSIM) [3], and (2) a technique that is based on the localization of individual fluorescent molecules, termed Stochastic Optical Reconstruction Microscopy (STORM [4], Photo-Activated Localization Microscopy (PALM) [5], or Fluorescence Photo-Activation Localization Microscopy (FPALM) [6]. In this paper, we describe the concept of STORM microscopy and recent advances in the imaging capabilities of STORM. 

S.W. Hell, J. Wichmami, Breaking the diffraction resolution limit by stimulated emission stimulated-emission-depletion fluorescence microscopy. Opt. Lett. 19, 780-782 (1994)... 

Stimulated emission depletion in two-photon exdted states... 

Figure 11.21 StimuLated emission depletion (STED) microscopy. The sample is excited using single-photon excitation (PUMP pulse) in a confocal microscope arrangement. A time-delayed DUMP pulse selectively depletes close to 100% of the exdted state population in a region around the focus of the PUMP pulse. Using this approach. Hell and co-workers were able to obtain a 5-fold reduction in the fluorescent spot size in the vertical (Z-direction) and a greater than a 2-fold reduction in the horizontal Y/X) direction, leading to a final image size of 97 by 104 nm...

Bain, A.J., Marsh, R.J., Armoogum, D.A., Porres, L., Mongin, O. and Blanchard-Desce, M. (2003). Time resolved stimulated emission depletion in two-photon excited states. BioChem. Soc. Trans. 31 1047-1051. 

Stimulated emission depletion (STED) microscopy is another microscopy approach to overcome the diffraction limitation of light microscopy by inhibiting fluorescence outside of the focal spot [9]. In this context, fluorescence is viewed as spontaneous light emission while stimulating emission via synchronized laser... 

Ear-field nanoscopic measuring technique Ear-field optical nanoscopic measuring technique Laser-induced fluorescence photobleaching anemometer Nanoscopy Stimulated emission depletion... 

Hell S, Wichmann J (1994) Breaking the dillraction resolution limit by stimulated emission stimulated-emission-depletion fluoreseenee mimoseopy. Opt Lett 19(11) 780... 

To realize the observation/detection on nanofluidics, the LIF with high resolution is a vital factor. With the release of stimulated emission depletion (STED) fluorescence microscope, the super-resolution LIF microscope on confocal manner, the high resolution at the order of nanometer was obtained [7, 8]. It was utilized to measure the velocity of fluorescent probes in nanofluidics and to observe the ion... 

Light microscopy is the oldest and the simplest imaging method. However, the lower resolution limit for conventional light microscopy lies above 200 nm. Its application to colloidal particles is, therefore, restricted to rather large colloids and aggregates of them. Even though recent developments, like stimulated emission depletion (STED) microscopy, have shifted the optical resolution limit below 100 nm (Hell 2007), light microscopy is not really relevant for the characterisation of colloidal suspensions. 

Apart from SNOM (or NSOM), two new, highly resolving techniques are emerging that deserve brief mention here. These are stimulated emission depletion (STED) using focal and doughnut-focal beam shapes, and the microscopy with super lenses out of negative index of refraction materials (NIMs). 

SD spinodal decomposition SEM scanning electron microscopy SNOM scanning near-field optical microscopy STED stimulated emission depletion SWNT single wall carbon nanotube TEM transmission electron microscopy... 

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