Lecturer: Prof. Hui Cao
Affliation: Department of Applied Physics
and Department of Physics, Yale University
Abstract:
Random scattering of light, e.g., in paint,
cloud and biological tissue, is a common
process of both fundamental interest
and practical relevance. Experimentally
we observed the position-dependent
diffusion inside an open disordered
medium. Interference of light in time-
reversed paths results in renormalization
of diffusion coefficient. To control light
propagation in a disordered waveguide,
we selectively couple the incident light
to open or closed transmission channels.
The light intensity distribution inside the
disordered medium changes from an
exponential decay to a linear decay and
to a profile peaked near the center of
the waveguide. Finally we realized a
chip-scale spectrometer with disordered
nanostructures. The wavelength-
dependent speckle patterns are used as
a fingerprint to reconstruct the input
spectra. A broadband enhancement of
spectral resolution is achieved via
multiple scattering of light.