Brewster angle prism retroreflectors for cavity enhanced spectroscopy

Area of Science:

• Optics and Photonics
• Laser Physics
• Optical Engineering

Background:

• High finesse optical cavities are crucial for precision measurements and laser stabilization.
• Traditional cavity designs often face limitations in specific spectral regions or with alignment sensitivity.
• Prism retroreflectors offer a novel approach to cavity design, potentially overcoming some existing challenges.

Purpose of the Study:

• To fully describe the design of a high finesse optical cavity utilizing two prism retroreflectors.
• To present optical beam propagation calculations for determining prism specifications and beam characteristics.
• To analyze the sensitivity of the cavity's optic axis to alignment and fabrication errors and quantify material dispersion effects.

Main Methods:

• Detailed optical beam propagation calculations were performed to specify prism angles and dimensions.
• The astigmatic TEM00 beam size and its propagation within the cavity were analyzed.
• Sensitivity analysis was conducted for optic axis variations due to alignment and fabrication errors.
• Material dispersion effects were quantified for fused silica, calcium fluoride (CaF2), and barium fluoride (BaF2).

Main Results:

• The design specifications for prism angles and dimensions were determined through propagation calculations.
• The size and characteristics of the astigmatic TEM00 beam within the cavity were precisely calculated.
• The study quantified the sensitivity of the optic axis to prism alignment and fabrication tolerances.
• Experimental results with fused silica prisms closely matched the theoretical predictions.
• Material dispersion effects were quantified, indicating suitability for different spectral ranges.

Conclusions:

• The described optical cavity design using prism retroreflectors is validated by theoretical calculations and experimental results.
• The design demonstrates good agreement with experimental data, particularly for fused silica.
• Prisms made from CaF2 and BaF2 are predicted to be suitable for ultraviolet (UV) and mid-infrared (mid-IR) spectral applications, respectively.
• This work provides a foundation for developing advanced optical cavities for diverse spectral applications.