Ultra-coherent meta-emitter tailors arbitrary thermal wavefront

Area of Science:

• Photonics and Nanotechnology
• Thermodynamics and Thermal Engineering

Background:

• Conventional light manipulation struggles with incoherent thermal sources.
• Existing thermophotonics offer directional emission but lack arbitrary wavefront control.
• Controlling thermal wavefronts is crucial for advanced applications like focusing and holography.

Purpose of the Study:

• To develop a generalized method for designing meta-emitters enabling arbitrary thermal wavefront control.
• To overcome the inherent conflict between coherent light-field techniques and incoherent thermal radiation.
• To enable functionalities like thermal focusing and holography using tailored thermal emission.

Main Methods:

• Designing meta-emitters with coupled lossy and lossless outer boundaries.
• Utilizing a single-mode waveguide to couple surfaces and convert incoherent thermal photons to coherent surface waves.
• Independently optimizing photon lifetime and propagation length via designer surface modes for spatial coherence engineering.

Main Results:

• Experimental demonstration of near-diffraction-limited self-focusing thermal emission.
• Creation of quasi-2D high-quality thermal holography without speckle noise.
• Achieved spatial-multiplexed holography and suggested potential for spatial coherence exceeding 1000λ₀.

Conclusions:

• The proposed meta-emitter design provides a paradigm shift for integrating thermodynamic emission with photonic engineering.
• This work opens new avenues for developing information-rich thermal radiation technologies.
• The ability to engineer thermal wavefronts paves the way for advanced optical functionalities from thermal sources.