Control of Energy Density inside a Disordered Medium by Coupling to Open or Closed Channels
Raktim Sarma1, Alexey G Yamilov2, Sasha Petrenko2
1Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
Physical Review Letters
|September 3, 2016
Summary
Researchers precisely controlled light intensity within random scattering systems using adaptive wavefront shaping in silicon waveguides. This breakthrough allows for tailored light energy distribution, impacting light-matter interactions in turbid media.
Area of Science:
- Photonics
- Materials Science
- Waveguide Optics
Background:
- Controlling light propagation in scattering media is challenging.
- Disordered systems typically exhibit complex light intensity distributions.
- On-chip manipulation of light in nanostructured waveguides is an active research area.
Purpose of the Study:
- To demonstrate efficient experimental control of light intensity distribution within a random scattering system.
- To explore the capabilities of adaptive wavefront shaping in silicon waveguides.
- To investigate the impact of selective mode coupling on energy storage and distribution.
Main Methods:
- Application of adaptive wavefront shaping technique.
- Utilizing a silicon waveguide with integrated scattering nanostructures.
- Employing an on-chip coupling scheme for access to all input spatial modes.
- Selective coupling of incident light to open or closed channels within the disordered system.
Main Results:
- Achieved efficient control over light intensity distribution.
- Varied the total stored energy within the system by a factor of 7.4.
- Modified the energy density distribution profiles (exponential, linear, and centrally peaked).
- Demonstrated selective coupling to open and closed channels.
Conclusions:
- The study successfully demonstrates on-chip control of light intensity in random scattering systems.
- Adaptive wavefront shaping in silicon waveguides offers a powerful tool for manipulating light.
- This platform facilitates enhanced control over light-matter interactions in turbid media.
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