**Robert A. Jackson 1,\* and Zsuzsanna Szaller 2,\***


Received: 31 August 2020; Accepted: 31 August 2020; Published: 3 September 2020

**Abstract:** This special issue features eight papers which cover the recent developments in research on lithium niobate. Papers are divided into three groups based on their topic.

**Keywords:** photorefractive properties; defect structure; lithium niobate
