Optically induced quantum transitions in direct probed mesoscopic NbSe₂ for prototypical bolometers

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Superconducting transition-edge sensors (TES) are advanced detectors for electromagnetic radiation, known for low thermal noise.
• Metallic transition metal dichalcogenides, like NbSe2, exhibit interesting low-temperature superconducting properties.
• NbSe2 has not been previously explored for use in TES devices.

Purpose of the Study:

• To demonstrate the feasibility of using NbSe2 as a superconducting absorber in a TES framework.
• To investigate the optical absorption and thermal properties of NbSe2 in a superconducting state.
• To explore the potential of NbSe2 for novel superconducting radiation detector applications.

Main Methods:

• Fabrication and testing of NbSe2-based superconducting absorbers.
• Characterization of the superconducting phase transition under bias.
• Optical absorption measurements with varying wavelengths.
• Raman spectroscopy for thermal conductivity determination (in-plane and out-of-plane).

Main Results:

• Proof-of-concept demonstration of NbSe2's ability to transduce light into heat via its superconducting transition.
• Observed a thermodynamic superconducting phase transition in NbSe2, switching to the normal state when biased below its critical temperature.
• Demonstrated wavelength-dependent optical absorption properties of NbSe2.
• Empirically determined in-plane and out-of-plane thermal conductivity using Raman spectroscopy.

Conclusions:

• NbSe2 shows promise as a material for superconducting radiation detectors.
• The study validates the use of NbSe2 within the transition-edge sensor (TES) architecture.
• Further research into NbSe2-based detectors is warranted for advanced radiation detection.