Single-Detector Spectrometer Using a Superconducting Nanowire.

Area of Science:

• Optics and Photonics
• Quantum Technologies
• Spectroscopy

Background:

• Traditional spectrometers often rely on complex wavelength multiplexing optics, increasing size and cost.
• Superconducting nanowire single-photon detectors offer high sensitivity but are typically used in systems requiring optical components.
• Developing compact, high-resolution spectroscopic instruments is crucial for advanced sensing and imaging applications.

Purpose of the Study:

• To demonstrate an optics-free spectrometer by leveraging computational spectroscopy and a dynamic detector.
• To integrate a superconducting nanowire's tunable quantum efficiency into a mathematical framework for spectral analysis.
• To achieve simultaneous spectral and time-of-flight measurements for enhanced functionality.

Main Methods:

• Employed a computational spectroscopic strategy combined with a broadband-responsive dynamic detector.
• Mapped the tunable quantum efficiency of a superconducting nanowire into a matrix to form a solvable equation.
• Utilized an optics-free setup for spectral measurements and time-of-flight analysis.

Main Results:

• Successfully demonstrated an optics-free single-detector spectrometer with broadband spectral responsivity from 660 to 1900 nm.
• Achieved sub-10 nm spectral resolution in the telecom range, surpassing existing infrared single-photon detector capabilities.
• Simultaneously performed precise time-of-flight measurements and demonstrated a spectral LiDAR with eight channels.

Conclusions:

• The developed spectrometer scheme significantly reduces complexity and physical footprint by eliminating wavelength multiplexing optics.
• This approach enables multifunctional spectroscopy and paves the way for advanced applications of superconducting nanowire detectors.
• Represents a conceptual advancement for on-chip spectroscopy, spectral imaging, and integrated photonic systems.