Demonstration of a high-resolution virtually imaged phased array in the far-infrared

Area of Science:

• Physics
• Astronomy
• Spectroscopy

Background:

• Far-infrared (FIR) spectroscopy is crucial for astrophysical studies.
• Compact, high-resolution spectrometers are needed for space-borne applications.

Purpose of the Study:

• To measure the spectral performance of a silicon-based virtually imaged phased array (VIPA) at FIR wavelengths.
• To assess the potential of FIR VIPAs for astrophysical investigations.

Main Methods:

• In-house characterization of a compact, cryogenically cooled (4 K) silicon VIPA.
• Utilized a quantum-cascade laser (115.7 µm) and a pyroelectric detector for measurements.

Main Results:

• Achieved a spectral resolution of approximately R∼16,300.
• Demonstrated the compact nature and lack of moving parts in the FIR VIPA.

Conclusions:

• The FIR VIPA provides an instantaneous multi-element spectrum dispersed in exit angle.
• This technology has transformative potential for velocity-resolved astrophysics in balloon- and space-borne missions.