Novel temperature operated electrooptical materials based on K2ZnCl4: PVA polymer nanocomposites

TL;DR

This study reports temperature-dependent electrooptical properties of K2ZnCl4 nanocrystals embedded in PVA, revealing enhanced efficiency within a specific temperature range due to structural modulation.

Contribution

It introduces novel temperature-operated electrooptical nanocomposites based on K2ZnCl4 with detailed analysis of size, content, and temperature effects on EOE performance.

Findings

Maximum EOE efficiency of 1.4 pm/V at 375-420 K

EOE efficiency depends on nanocrystal size and content

Bulk-like EOE performance achieved at 1200 nm size

Abstract

We have discovered significant temperature anomalies of the linear electrooptical (EOE) coefficients for the K2ZnCl4 nanocrystallites embedded into the polymer matrices. The EOE efficiency was operated by external dc-electric field and UV polarized laser light. The maximal enhancement of EOE output was achieved within the temperature range 375 K-420 K. This temperature range corresponds to existence of incommensurate structural modulation. The maximally achieved field induced EOE efficiency was equal to about 1.4 pm/V for off-diagonal EOE tensor component. The size and NC content dependences have been explored for the size range (20 nm-1500 nm) and contents varying within the 25%-35%. For the sizes about 1200 nm, the EOE is commensurable with the EOE of the bulk crystals and is equal to about 0.6 pm/V.