Electrically tunable waveguide laser based on ferroelectric liquid crystal

Laser action in a waveguide configuration has been demonstrated in a planar alignment cell of dye-doped chiral smectic liquid-crystal mixtures with a short pitch helical structure. In this configuration, doped dye can effectively be excited by a pump beam illuminating perpendicularly the helical axis and the laser light emitted along the helical axis propagates in the waveguide. Lasing wavelength can be tuned by adjusting the periodicity of the helical pitch upon applying the electric field.