1 / 33

Advanced Optical Microscopy lecture 4. February 2013 Kai Wicker

Advanced Optical Microscopy lecture 4. February 2013 Kai Wicker. Exam: written exam 26 February 2013 exact time and place will be announced by email.

siusan
Download Presentation

Advanced Optical Microscopy lecture 4. February 2013 Kai Wicker

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Advanced Optical Microscopylecture4. February 2013Kai Wicker

  2. Exam:written exam26 February 2013exact time and place will be announced by email

  3. Today:The quantum world in microscopy1. Photon anti-bunching2. Interaction-free measurements3. Entangled photons, parametric down-conversion4. Beating shot-noise5. Entangled two-photon microscopy

  4. 1. Photon anti-bunching

  5. Normal fluorescence Jablonski diagram Absorption… … and spontaneous emission

  6. Photon anti-bunching:- only 1 photon per emitter and excitation pulse - sub-Poissonian (!) statistics 1.0 anti-bunching

  7. Possible applications of photon anti-bunching:- single molecule localisation: is it really just one single molecule?- super resolution imaging exploiting sub-Poissonian statistics

  8. Super resolution imaging exploiting sub-Poissonian statistics a) Pulsed excitation and synchronised detection b) + d) Two-pixel correlations c) + e) Three-pixel correlations

  9. Super resolution imaging exploiting sub-Poissonian statistics a) + d) Conventional fluorescence image b) + e) Second order anti-bunching c) + f) Third order anti-bunching

  10. 2. Interaction-free measurementsSeeing without light

  11. Fabry-Perot resonator Mirror Transmitted light Reflected light

  12. Fabry-Perot resonator Mirror Transmitted light Transmitted light Reflected light Transmitted light Reflected light

  13. Fabry-Perot resonator Mirror

  14. Fabry-Perot resonator Mirror opposite phase  cancellation

  15. Fabry-Perot resonator Case 1 Onemirror Case 2 Twomirrors, resonator Interaction-freemeasurement Case 3 Twomirrorswithobstacle

  16. Experiment: Imaging photographic film withoutexposingitto light „sample“-film „detector“-film scanarea

  17. Experiment: Imaging photographic film withoutexposingitto light

  18. 3. Entangled photons, parametric down-conversion

  19. Coherent super-positions of states: “click”

  20. parametric down-conversion Position entanglement! Image: European Space Agency

  21. 4. Beating shot-noise

  22. Beating shot-noise Position entanglement! Intensity distributions are correlated, even down to Poisson noise!! Image: Alessandra Gatti, Enrico Brambilla, and Luigi Lugiato, “Quantum Imaging,” 2007

  23. Beating shot-noise Illumination Quantum image: Classical image: Not correlated! Identical! Weakly absorbing object

  24. Beating shot-noiseimaging a weakly absorbing object

  25. Beating shot-noiseimaging a weakly absorbing object Simulation Quantum image: SNR 3.3 Sample Classical image: SNR 1.2

  26. Beating shot-noiseimaging a weakly absorbing object Experiment Sample: π-shapedtitaniumdeposition Classical image: SNR 1.2 Quantum image: SNR 1.7

  27. 5. Entangled two-photon microscopy

  28. Normalfluorescence Jablonski diagram NO absorption…

  29. 2-photonfluorescence Jablonski diagram 2-photon absorption… … and spontaneous emission

  30. 2-photonfluorescence • Classical: • 2-photon absorption requires two photons to be present simultaneously. • The probability for this growsquadratically with intensity. • It will only occur where the local intensity is high. • Quantum: • 2-photon absorption requires two photons to be present simultaneously. • This isachievedthrough temporal coincidenceofentangledphotons.

  31. Entangled two-photon microscopy Comparissonof different imagingmodalities:

  32. Entangled two-photon microscopy

  33. End of lecture

More Related