Abstract
AbstractWe demonstrate a new concept for reconfigurable nanophotonic devices exploiting ultrafast nonlinear control of shaped wavefronts in a multimode nanomaterial consisting of semiconductor nanowires. Femtosecond pulsed laser excitation of the nanowire mat is shown to provide an efficient nonlinear mechanism to control both destructive and constructive interference in a shaped wavefront. Modulations of up to 63% are induced by optical pumping, due to a combination of multimode dephasing and induced transient absorption. We show that part of the nonlinear phase dynamics can be inverted to provide a dynamical revival of the wavefront into an optimized spot with up to 18% increase of the peak to background ratio caused by pulsed laser excitation. The concepts of multimode nonlinear switching demonstrated here are generally extendable to other photonic and plasmonic systems and enable new avenues for ultrafast and reconfigurable nanophotonic devices.
Highlights
Many of the available photonic technologies are based on perfectly regular, ordered structures such as waveguides, photonic crystals and metamaterials
We demonstrate a new concept for reconfigurable nanophotonic devices exploiting ultrafast nonlinear control of shaped wavefronts in a multimode nanomaterial consisting of semiconductor nanowires
We extend the idea of multimode dephasing by combining it with wavefront shaping to control both the destructive and constructive interference in a shaped light field on ultrafast time scale
Summary
Many of the available photonic technologies are based on perfectly regular, ordered structures such as waveguides, photonic crystals and metamaterials. Knowledge of the transmission matrix,[11,12] along with an ability to completely control the incident light,[10] would allow the selection of any desired output, turning an opaque medium into a versatile optical element. To the interest for biomedical imaging,[13,14,15] wavefront shaping shows promise for reconfigurable optical elements[16,17,18,19,20] and control of random lasers.[21] While initial work concentrated on monochromatic continuous-wave radiation, focusing through opaque scattering media has been achieved using ultrashort pulses[22,23] and polychromatic light.[24]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
