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Module ‐ Saturation Absoption Spectroscopy Baseplate

UMass Ion Trappers edited this page Feb 2, 2025 · 6 revisions

Rb SAS Real

Saturated absorption spectroscopy (SAS) is a common technique for locking and stabilizing lasers via atomic transitions.

The entire SAS setup is built using PyOpticL in a 1/2 mounted optics standard. The layout includes the following components:

  • Input Alignment:

    • Two optional input mirrors for downstream alignment.
    • A half-wave plate to branch off power via a polarizing beam splitter (PBS).
  • Probe Beam:

    • A beam sampler reflects a small fraction of the light to transmit through the Rb cell as the 'probe' beam.
    • A half-wave plate rotates the vertical polarization to horizontal, allowing the probe beam to pass through the PBS and be detected by the photodiode.
  • Pump Beam:

    • The majority of the light transmits through the beam sampler becoming the 'pump' beam.
    • The vertically polarized pump beam then reflects off the PBS, counter propagating the pump beam.
  • Optional Features:

    • The pump power can be reused by fiber coupling to a wavemeter.

Rb SAS Rb SAS Real

Modular Saturated Absorption Spectroscopy Baseplates compiled at different scales image

Files and Drawings

Saturation_Absorption_Spetroscopy.step

Saturation_Absorption_Spetroscopy_topview.pdf

Rb SAS drawing

Vapor cell enclosure for heating

To increase the signal to noise of the Rb spectrum, we heat the vapor cell to over 100C. Insulating the cell make it easier to heat, so we use a 3D printed enclosure to hold the Rb vapor cell made from 'High temperature' SIRAYA Tech Professional UV Resin.