Table 1 Summary of integrated beam delivery methods

From: Photonic integrated beam delivery for a rubidium 3D magneto-optical trap

Beam delivery method

Beam delivery

Beam properties

Trapping beam overlap volume

Beam delivery distancea

Number of retroreflectors

Optical accessb

Atom number

Conventional MOT31

Six free-space (FS) beams

Collimated Gaussian beams, diameters ~30 mm

~104 mm3

N/A

3

5

~108

Diffraction grating MOT35

Fiber input, one collimated beam and 3 diffracted beams

Input FS beam 20 mm diameter

103 mm3

16 cm

0

3–4

6×107

90° Pyramid39

Fiber input, one collimated beam and 5 reflected beams

Input FS beam 4.2 mm diameter

10 mm3

3 cm

0

0

104

PIC emitter, MS, GMOT37

Fiber input, one PIC-delivered beam and 3 diffracted beams

Diverging beam after MS. Diameter 20 mm, flat-top

340 mm3

15 cm

0

3

3×106

SiN beam delivery PIC (this work)

Fiber input, three PIC-delivered beams

Collimated,2.5 ×3.5 mm2,uniform intensity

22 mm3

4 cm

3

4-5

1.3×106

  1. Comparison of beam delivery methods for a rubidium 3D MOT. Trapping beams can be delivered with free-space optics or in a compact geometry using a diffraction grating, metasurface, etched pyramid, or a photonic chip. The MOT forms within a trapping volume formed by the beam intersection.
  2. aApproximate distance for beam expansion and routing between a single fiber-coupled input and the trap center.
  3. bNumber of sides available for optical access without blocking trapping beams, assuming a cube-like vacuum cell with the atomic vacuum source located at one face of the cell.
Back to article page