Correction for phase-shift deviation in a complex Fourier-transform integrated-optic spatial heterodyne spectrometer...

Area of Science:

• Optics and Photonics
• Spectroscopy
• Waveguide Technology

Background:

• Spatial heterodyne spectroscopy (SHS) offers high-resolution spectral analysis.
• Planar waveguides are increasingly utilized in integrated optical systems.
• Controlling phase shifts is crucial for interferometric techniques.

Purpose of the Study:

• To demonstrate spectrum retrieval using a planar waveguide spatial heterodyne spectrometer (SHS) with an active phase-shift scheme.
• To experimentally validate the performance of this novel SHS configuration.

Main Methods:

• Implementation of an active phase-shift scheme with phase shifts distributed around π/2.
• Experimental setup utilizing an SHS with 32 interleaved Mach-Zehnder interferometers.
• Operation with a free spectral range of 625 GHz and phase shifts ranging from 0.71 to 2.2 radians.

Main Results:

• Successful spectrum retrieval was achieved using the planar waveguide SHS with the active phase-shift scheme.
• Experimental validation confirmed the feasibility of the proposed method.
• The implemented phase shifts closely approximated the target of π/2 radians.

Conclusions:

• The active phase-shift scheme is effective for spectrum retrieval in planar waveguide SHS.
• This approach enhances the capabilities of integrated spectrometers.
• The experimental results support the theoretical framework for phase-controlled SHS.