Correlation of film thickness to optical band gap of Sol-gel derived Ba0.9Gd0.1TiO3 thin films for optoelectronic applicationsYen Chin Teh, Ala’eddin A. Saif, Zul Azhar Zahid Jamal and Prabakaran PoopalanEPJ Web Conf., 162 (2017) 01042DOI: https://doi.org/10.1051/epjconf/201716201042