Microfluidic directional emission control of an azimuthally polarized radial fibre laser

Alexander M. Stolyarov (1, 2, 3) , Lei Wei (1, 2) , Ofer Sharipa (2, 1) , Fabien Sorin (1, 2, 4) , Song L. Chua (1, 2, 5) , John D. Joannopoulos (1, 2, 6) , Yoel Fink (1, 2, 7)

1 Research Laboratory of Electronics
2 Institute for Soldier Nanotechnologies
3 SEAS - Harvard John A. Paulson School of Engineering and Applied Sciences
4 SVI - Surface du Verre et Interfaces
5 Department of Electrical Engineering and Computer Science
6 Department of Physics [MIT Cambridge]
7 Department of Materials Science and Engineering

Lasers with cylindrically symmetric polarization statesare predominantly basedon whispering-gallerymodes1-7, characterized by high angular momentum and dominated by azimuthal emission.Here azero angular momentum laserwith purely radial emission is demonstrated.An axially invariant, cylindrical photonic bandgap fibrecavity8filled with a microfluidic gain medium plug is axially pumped, resulting in a unique radiating field pattern characterized by cylindrical symmetry and a fixed polarization pointed in theazimuthal direction.Encircling the fibre core is anarray ofelectrically contacted and independently addressable liquid crystal microchannelsembedded in the fibrecladding. Thesechannels modulate the polarized wavefront emanating from the fibre coreleading toa laser with a dynamically controlled intensity distribution spanning the full azimuthal angular range. This new capability,implemented monolithicallywithin a single fibre, presents opportunities ranging from flexible multidirectional displaysto minimally invasive directed light delivery systems for medical applications

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Alexander M. Stolyarov, Lei Wei, Ofer Sharipa, Fabien Sorin, Song L. Chua, et al.. Microfluidic directional emission control of an azimuthally polarized radial fibre laser. Nature Photonics, 2012, 6, pp.229-233. ⟨hal-00666119⟩