Spatial mode demultiplexing for super-resolved source parameter estimation

Area of Science:

• Optics and Photonics
• Astronomy and Astrophysics

Background:

• Accurate measurement of binary star separations is crucial for understanding stellar evolution and galactic dynamics.
• Current techniques face limitations in resolving sources close to or below the diffraction limit.

Purpose of the Study:

• To introduce and validate a novel optical method for high-precision spatial separation estimation of incoherent sources.
• To demonstrate the capability of the developed technique for simultaneous separation and relative power estimation.

Main Methods:

• Utilizing a multi-planar light converter (MPLC) for spatial mode demultiplexing (SPADE).
• Extending the SPADE technique with higher-order Hermite-Gaussian modes.
• Applying the method to estimate separations of incoherent sources, including those below the diffraction limit.

Main Results:

• Achieved super-resolution, resolving sources at separations 90x lower than the diffraction limit.
• Demonstrated simultaneous estimation of source separation and relative power (up to 20 dB difference).
• Validated the system's capability by incorporating information from higher-order modes.

Conclusions:

• The SPADE technique offers unprecedented precision in resolving closely spaced incoherent sources.
• This method holds significant potential for advancing astronomical imaging, particularly for binary star systems.
• The ability to perform simultaneous separation and power estimation enhances its utility in astrophysical observations.