Mallory Traxler April 2013

2/39  Continuous atom laser  Continuous, coherent stream of atoms  Outcoupled from a BEC  Applications of atom lasers:  Atom interferometry Electromagnetic fields Gravitational fields  Precision measurement gyroscopes  Atom lithography

3/39  Guide α  Experimental apparatus  Experiments in guide α  Rydberg atom guiding  Design and manufacture of guide β  Improvements from guide α’s design  Outlook

4/39 α

5/39 α

6/39

7/39  Φ pmot ≈3x10 9 s -1  ≈22 m/s  2D+ MOT  Φ mmot ≈4.8x10 8 s -1  2.2 m/s to 2.9 m/s

8/39  Detect atoms at the end  Uses pulsed probe (2  3) and probe repumper (1  2)  Optimize atoms in the guide

9/39  Three lasers for excitation  Repumper to get back to bright state  5S 1/2  5P 3/2  480 nm to 59D  Ionize  Voltages on electrode, guard tube, MCP direct ions upward to MCP for detection

10/39 α

11/39  High n-principal quantum number  Data here with n=59  Physically large  r~n 2  Very susceptible to electric fields  α~n 7  Strong interactions  Other Rydberg atoms  Blackbody radiation

12/39  Excitation to 59D  Variable delay time, t d  MI or FI  Camera gated over ionization duration

13/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

14/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

15/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

16/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

17/39  Penning ionization  Remote field ionization  Initial  delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

18/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

19/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

20/39  Penning ionization  Remote field ionization  Initial  Delayed  Thermal ionization  (Radiative decay)  Microwave ionization  Field ionization

21/39  Vary t d from 5 μ s to 5 ms  τ MI =700 μ s  τ 59D5/2 =150 μ s

22/39  State-selective field ionization  Different electric field needed for different states  59D peak broadens  State mixing

23/39  Rydberg atoms excited from ground state atoms trapped in guide  Observe Rydberg guiding over several milliseconds using microwave ionization and state selective field ionization  Numerous phenomena from Rydberg atoms within the guide

24/39 β

25/39  Improvements over guide α  Zeeman slower  No launching  Magnetic injection  Mechanical shutter β

26/39  Standard 6-beam MOT  Fed by Zeeman slower  Factor of 6.6 brighter  Expect closer to 10x

27/39  Most complicated part of the design  4 racetrack 2MOT coils  8 injection coils  Built-in water cooling  Magnetic compression  Mechanical shutter

28/39  4 racetrack coils produce quadrupole magnetic field  Holes  Optical access  Venting of internal parts  Shutter  2 locks for stationary shutter

29/39  8 injection coils of varying diameters  Fits inside 2MOT coil package  Water cooling for all  Tapered inside and out

30/39  Magnetic compression  Mount for waveplate-mirror  Stationary shutter

31/39  Hand-turned on lathe  2MOT coils on form  Injection coils directly on mount  Labeled with UHV compatible ceramic beads

32/39  High current power supply  Split off 2-3 A for each coil  Adiabatically inject atoms into the guide

33/39  21 equally spaced silicon surfaces  Bring guided atomic flow closer to these surfaces  Atoms not adsorbed onto surface rethermalize at lower temperature

34/39  Fully constructed  Preliminary tests well on the way  Good transfer of atoms into the 2MOT  Need Zeeman slower and 2MOT working simultaneously to optimize β

35/39

36/39  Increase capture volume of Zeeman slower  Reduce transverse velocity by factor of x, increase density by factor of x 2  Most optics already in place

37/39  Potential barrier at the end of the guide  Form BEC upstream  Use coil to create potential  Study BEC loading dynamics, number fluctuations  Later use light shield barrier  Tunnel atoms through to make first continuous atom laser

38/39  PI  Prof. Georg Raithel  Former Post Docs  Erik Power  Rachel Sapiro  Former Grad Students (on this project)  Spencer Olson  Rahul Mhaskar  Cornelius Hempel  Recent Ph.D.  Eric Paradis  Graduate Students  Andrew Cadotte  Andrew Schwarzkopf  David Anderson  Kaitlin Moore  Nithiwadee Thaicharoen  Sarah Anderson  Stephanie Miller  Yun-Jhih Chen  Current Undergraduate  Matt Boguslawski  Former Undergrads  Varun Vaidya  Steven Moses  Karl Lundquist

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