Objective:

To present a new chaos-assisted computational spectrometer that breaks the trade-off between size, resolution, and bandwidth.

Approach:

• Device Design: The spectrometer is a compact device measuring 20 × 22 μm², utilizing a deformed microcavity shaped as a Limaçon of Pascal to support chaotic light propagation.
• Performance Metrics: Achieves a spectral resolution of 10 picometers across a 100 nm bandwidth, with a record-high bandwidth-to-resolution ratio per footprint.
• Operational Efficiency: Operates at a low power consumption of 16.5 mW and avoids bulky cascaded structures.
• Adaptability: The design allows for the replacement of grating couplers with edge couplers, extending operational bandwidth beyond 300 nm.

Key Findings:

• The use of chaotic mode mixing creates a diverse and decorrelated response matrix for spectral reconstruction.
• The system can be tuned across silicon's transparent window or adapted to other photonic materials.

Interpretation:

Chaos is utilized as a beneficial feature for improved spectral performance, supplying the random sampling behavior critical to the spectrometer's performance.

Limitations:

• The study does not address long-term stability or practical deployment challenges in real-world environments.

Conclusion:

The design offers a pathway for portable, low-power spectral sensing, potentially enabling chemical and biomedical sensing in real-world environments.

Sources:

• Light: Science & Applications