Femtosecond laser-induced crystallization in Er/Yb:BaTiO3 perovskite films: Effects on the optical and electrical properties

Abstract

Femtosecond laser-induced crystallization in Er3+/Yb3+:BaTiO3 (BTEY) perovskite films has sparked significant research interest in materials science and photonics, driven by the need for innovative techniques to control material properties and exploit their potential. Our study delves into this burgeoning area by demonstrating the controlled crystallization of amorphous BTEY thin films under femtosecond laser (fs-laser) irradiation at 1030 nm. The threshold fluence to achieve laser processing was determined as approximately 1.1 J/cm2 at 1 kHz, as well as the irradiation conditions for crystallization (pulse energy, repetition rate, and scanning speed), whose background mechanism is discussed. Our Raman spectroscopy analysis confirmed crystallization when irradiation was carried out at 1 kHz repetition rate, while no evidence of the crystalline phase of BTEY emerged at 1 MHz irradiation. Moreover, our results reveal a remarkable increase in luminescence enhancement and surface potential (∼65 mV) in the film. These outcomes represent a significant breakthrough with relevant implications for advanced photonic devices like modulators and detectors. By harnessing fs-laser pulses for BTEY crystallization, our findings offer new avenues for practical device applications.