1. Improvements to the Dipole Blockade Mallory Walker University of Michigan REU 2006 Georg Raithel SB149 http://cold-atoms.physics.lsa.umich.edu/

2. Introduction to Rydberg Atoms Excited; high n Very responsive to E and B fields Large van der Waals interaction potentials, which scale as n 11 /R 6 Picture from PRL 95, 253002 (2005)

3. Introduction to Dipole Blockade Finite range of vdW One atom per “bubble”

4. Counting Statistics Measure of effectiveness of blockade Q≡ ≡ Q<0 indicates sub-Poissonian Best yet is Q=-0.52

5. External Cavity Diode Laser My solo project for the summer Replacement for the old 5S  5P laser Specs Homemade Nearly as good Much cheaper Finished in week 8

6. External Cavity Diode Laser

7. Shop Projects

8. My Laser

9. Lasers for the Blockade Need quality lasers with narrow linewidth Realign every day; ensure maximum power output Lock the lasers Some locks extremely sensitive, especially 5S  5P laser

10. Current Modulating Circuit Reduced linewidth by factor of 4-5 Made a duplicate for the 5S  5P laser Peak lock instead of side lock Changed switch location

11. Circuit Diagram

12. Noise Difference ~1.4 MHz~600 kHzLinewidth

13. Dipole Blockade Optical Table AnyQuestions?AnyQuestions?