G.B. Hadjichristov¹, I.G. Marinov¹, A.G. Petrov¹, S. Marino², C. Versace^2,3, N. Scaramuzza^2,3
1Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria
²CNR-IPCF UoS di Cosenza, Licryl Laboratory, and Centro di Eccellenza, CEMIF.CAL, Universitá della Calabria, 87036 Rende (CS), Italy
³Dipartimento di Fisica, Universit\`{a} della Calabria, Via Pietro Bucci, Cubo 31C, 87036 Rende (CS), Italy

Abstract. We report on low-voltage, high-contrast amplitude/phase modulators of laser radiation on the basis of microscale polymer-dispersed liquid crystal (PDLC) single layers providing interference contrast enhancement. The modulators were prepared from liquid crystal (LC) E7 in the solid matrix of UV-cured polymer NOA65. Operating at low voltages, E7/NOA65 single-layered PDLC films of thickness 10-25 μm and mean diameter of LC droplets up to 50 μm are capable of producing a large phase shift up to π/2 for the propagating laser light. This property is very attractive for linear and non-linear optical applications. The precise spatial control of droplet size along the film thickness allows the linear droplet-size gradient single-layered PDLC films to be used for tunable spatial light modulators and other devices for active control of laser radiation.

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