1 / 30

Simulation of “Slow Light” and the beginnings of Quantum Memory

Simulation of “Slow Light” and the beginnings of Quantum Memory. Herbert Weller C’06. Olympic Sprinter. E/M Wave in a Vacuum. 3x10 8 m/s or 300000000 m/s. 17 m/s. See Demos. The Circuit. Instead of a medium we have the length Δ x for each phase Shifter circuit.

isabel
Download Presentation

Simulation of “Slow Light” and the beginnings of Quantum Memory

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. Simulation of “Slow Light” and the beginnings of Quantum Memory Herbert Weller C’06

  2. Olympic Sprinter E/M Wave in a Vacuum 3x108 m/s or 300000000 m/s 17 m/s

  3. See Demos

  4. The Circuit Instead of a medium we have the length Δx for each phase Shifter circuit. Or the “distance” passed per unit time.

  5. Phase Shifter • The circuit provides a group delay T for a signal limited to a bandwidth of 1/T T=2RC Transfer Function 

  6. Group Velocity Java Applet • http://gregegan.customer.netspace.net.au/APPLETS/20/20.html

  7. Group velocity in terms of k to the left and in terms of ω below

  8. Wave propagation @ different velocities

  9. “Slow Light” or a low group velocity happens when the group index is large “Fast light” occurs when the group index is less than one.

  10. Kramers-Kronig Relation • A change in absorption over a narrow spectral range must be accompanied by a change in refractive index over the same narrow range.

  11. Material Resonance

  12. Dispersion with in the Spectral line • Absorption grey, refractive index blue

  13. What is Electromagnetically Induced Transparency (EIT)?

  14. Material Resonance

  15. Two “dipole allowed” transitions and one “dipole non-allowed”

  16. Formal Mathematical explanation of group velocity, wave propagation, and the EIT condition, overhead projector. Senior Seminar Math.pdf

  17. Formal Mathematical relation of the circuit and the slow light system and the limitations of that system, overhead projector.

  18. Spectrum Condition • The descretized equation only works when the wave is smooth enough that the changes over Δx can be negated. or

  19. Circuit Configuration

  20. Constant propagation speed

  21. Decrease in propagation speed

  22. Increase in Propagation Speed

  23. EIT condition violation

  24. “Stopped Pulse”

  25. Future Possibilities • Quantum Memory? (Possibility) • Faster than Light Data Transmission (not a possibility with this method) • Laser Transmission with out absorption through walls or thick heterogeneous gases (not a possibility)

  26. Questions

  27. Acknowledgements • Sarah Matthews @ TTI International • Christi Sessions @ TRS Telco • Dr. Peterson • Wave Propagation and Group Velocity, Leon Brillouin, 1960 • Classical Electrodynamics, John David Jackson, 3rd Ed., 1999 • Simulation of Slow Light with Electronic Circuits, Am J. Phys • Demonstration of Negative Group Delays in a simple electronic circuit, Am J. Phys. 70, T. Nakanishi, K Sugiyama, and M. Kitano • Negative Group Delay and Superluminal Propagation: An Electronic Circuit Approach, IEEE Journal of Selected topics in Quantum Electronics, Vol. 9 , NO. 1, M. Kitano, T. Nakanishi, K. Sugiyama • “Slow” and “Fast” Light, Robert W. Boyd, Progress in Optics, Vol 43, 2002 • Electromagnetically Induced Transparency, S. Harris, Physics Today, July 1997

More Related