Fluorescence and lasing in an electric-field-induced periodic structure of a cholesteric liquid crystal

Journal Article · Thu Aug 01 00:00:00 EDT 2019 · Quantum Electronics (Woodbury, N.Y.)

DOI:https://doi.org/10.1070/QEL16898· OSTI ID:23004992

Shtykov, N. M.; Palto, S. P.; Umanskii, B. A.; Rybakov, D. O.

Fluorescence and lasing in a structure with an electric-field-induced spatially periodic director modulation in the plane of a planar-oriented layer of a cholesteric liquid crystal (CLC) is experimentally investigated. The thickness of the CLC layer is chosen close to the natural pitch of the cholesteric helix, which corresponds to the second Grandjean zone. The electric-field-induced periodic field of the CLC director leads to spatial modulation of the refractive index and the appearance of optical properties typical of 1D photonic crystals, when light propagating in the plane of the CLC layer experiences Bragg reflection. In polarised light, the induced spatial modulation of the refractive index manifests itself in the form of banded domains oriented in the plane of the CLC layer perpendicular to the original (unperturbed electric field) direction of the director in the centre of the layer. For the electric field strengths that correspond to fundamentally different distributions of the field of a CLC director, the fluorescence spectra of the DCM laser dye are studied both for different geometries (including the waveguide regime) and for different levels of optical pumping. In the range of electrical voltages corresponding to the induction of a spatially periodic photonic structure, multimode lasing in the waveguide regime is detected. It is shown that the mode composition of lasing depends on the electric field, which affects the properties of the distributed feedback. (paper)

• OSTI ID: 23004992
• Journal Information: Quantum Electronics (Woodbury, N.Y.), Vol. 49, Issue 8; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7818
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BRAGG REFLECTION
ELECTRIC FIELDS
ELECTRIC POTENTIAL
FLUORESCENCE
FLUORESCENCE SPECTROSCOPY
GEOMETRY
INDUCTION
LASERS
LAYERS
LIQUID CRYSTALS
MODULATION
ONE-DIMENSIONAL CALCULATIONS
OPTICAL PUMPING
PERIODICITY
REFRACTIVE INDEX
VISIBLE RADIATION
WAVEGUIDES