Studying a strontium MOT – group meeting 01-12-08 Studying a strontium MOT James Millen

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<ul><li> Slide 1 </li> <li> Studying a strontium MOT group meeting 01-12-08 Studying a strontium MOT James Millen </li> <li> Slide 2 </li> <li> Theory 689nm 7.6kHz Up to 13mins* *Yasuda, Katori Phys. Rev. Lett. 92, 153004 (2004) (5s 2 ) 1 S 0 461nm 32MHz (5s5p) 1 P 1 620Hz (5s4d) 1 D 2 0.33 (105Hz) (5s5p) 3 P 2 0.67 (213Hz) 3P13P1 679nm (1.4MHz) 707nm (6.4MHz) (5s6s) 3 S 0 3P03P0 7.6kHz Studying a strontium MOT group meeting 01-12-08 </li> <li> Slide 3 </li> <li> Using the photodiode One nW of light corresponds to (27.80.2)mV of signal The photodiode sees a solid angle of the emitted light Each atom scatters R photons Each atom emits a power Hence there are N A atoms </li> <li> Slide 4 </li> <li> Atom number experimental sequence Controlled by LabView via FPGA card MOT beams always on A)B-field &amp; slowing light off B) Slowing light on C) B-field and slowing light on D) B-field on, slowing light off E) B-field &amp; slowing light off Studying a strontium MOT group meeting 01-12-08 </li> <li> Slide 5 </li> <li> MOT atom number Rydberg &amp; plasma physics using ultra-cold strontium Strontium MOT I sat corresponds to 19mW of MOT beam power </li> <li> Slide 6 </li> <li> MOT atom number Rydberg &amp; plasma physics using ultra-cold strontium Strontium MOT </li> <li> Slide 7 </li> <li> Some preliminary results MOT lifetime Rydberg &amp; plasma physics using ultra-cold strontium Strontium MOT Black line I = I peak Blue line I = I average Green line I = I peak </li> <li> Slide 8 </li> <li> Studying a strontium MOT group meeting 01-12-08 Using the camera We use a pco. pixelfly qe CCD camera, with 1392x1024 pixels It has an internal shutter that shutters in about 8s Each pixel is 6.45m 2, and we use a 1:1 magnification Calculated counts per pixel per photon = 0.132 Allows us to calculate atom number, but also MOT size </li> <li> Slide 9 </li> <li> Studying a strontium MOT group meeting 01-12-08 Example C = N </li> <li> Slide 10 </li> <li> Studying a strontium MOT group meeting 01-12-08 Number and density measurements </li> <li> Slide 11 </li> <li> Time of flight measurement Studying a strontium MOT group meeting 01-12-08 Create a MOT, let it go, and after some variable time image it and record its width. Assume Gaussian cloud shape and velocity distribution T = 5.90.5mK (Doppler limit 4.8mK) </li> <li> Slide 12 </li> <li> Release and recapture A)MOT and slower light on (molasses) B) MOT coils on (MOT fills) C) Slower light off (8ms) D) MOT light off E) MOT light back on Studying a strontium MOT group meeting 01-12-08 </li> <li> Slide 13 </li> <li> Release and recapture Studying a strontium MOT group meeting 01-12-08 </li> <li> Slide 14 </li> <li> To do Studying a strontium MOT group meeting 01-12-08 Analyze more temperature data Investigate effect of intensity / detuning on temperature Get some decent density data Next: Turn on MCP Make some ions Make some Rydbergs </li> </ul>