# The dielectric constant of Na_{0.4}K_{0.6}Br and its large temperature variation

## TL;DR

This study investigates the significant temperature-dependent dielectric behavior of Na_{0.4}K_{0.6}Br, attributing it to changes in ionic polarizability, which is crucial for optical device applications.

## Contribution

It provides a quantitative analysis linking dielectric constant variation to ionic polarizability changes in Na_{0.4}K_{0.6}Br.

## Key findings

- Na_{0.4}K_{0.6}Br exhibits strong temperature variation of dielectric constant
- The variation is quantitatively explained by ionic polarizability changes
- Implications for optical device component design

## Abstract

Since polycrystals of alkali halides are highly useful as components in optical devices, a number of mixed crystals of NaBr and KBr have been prepared from melt by other workers. Among these crystals, it was reported that the polycrystal Na$_{0.4}$K$_{0.6}$Br exhibits the strongest temperature variation of the dielectric constant. Here, we show quantitatively that this is due to the temperature variation of the ionic polarizability.

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Source: https://tomesphere.com/paper/1705.00845