Semiconductor nanowire lasers with a broadband and continuous wavelength tunability are highly desirable for integrated photonic and optoelectronic devices. Despite tremendous efforts and wide demonstration of past decades, however, current research still relies on the corporation of several spatially separating different nanowires on a single device to realize a broadly tunable laser, which largely restricts the further miniaturization and integration of on-chip photonic devices. The realization of a broadly tunable laser in single nanowire is of great importance but very challenging.

Recently, a researcher group from Shanghai Institute of Optics and Fine Mechanics of Chinese Academy of Sciences (CAS), Nanjing Xiaozhuang University and Shanghai Advanced Research Institute of CAS, realized a broadly and continuously tunable nanolaser utilizing single perovskite alloy nanowire. The article was published in Nano Energy.

In this work, researchers constructed single perovskite alloy nanowire with a widely tunable bandgap (2.41-2.82 eV) through a solid-solid anion-diffusion process. The as-synthesized nanowires have a regularly geometrical structure and widely tunable PL emission along the length, which makes them ideal candidates for the achievement of a broadly tunable nanowire lasers.

Under the excitation of a 400 nm femtosecond pulsed laser, a broadly tunable nanolaser from 480 to 525 nm was clearly observed from single perovskite nanowire with different spots along the length serving as both optical cavity and a gain media.

Also, this work analyzed the atomic-scale anion diffusion paths with a small activation energy via the density functional theory (DFT) calculations in theory, and studied the energy transfer mechanism of single perovskite nanowire through the time-resolved photoluminescence measurements. These analyses are important for clarifying the underlying mechanism of ion and carrier migrations, which has a pronounced influence on their crystal structures and thus the physical properties. (optical, electrical, electronic, magnetic, optoelectronic, etc.)

This work demonstrated a widely tunable laser of single nanowire, and thus activated the development of bandgap gradient nanowire tunable lasers and clarified the mechanism and kinetics of anion and carrier diffusion in single perovskite alloy nanowire.

This work was supported by the National Natural Science Foundation of China, the Youth Top-notch Talent Support Program in Shanghai.

A broadly tunable nanolaser from single perovskite alloy nanowire.(Image by SIOM)

Article website:
https://doi.org/10.1016/j.nanoen.2020.104641

Contact:
Mr. CAO Yong
General Administrative Office
Shanghai Institute of Optics and Fine Mechanics, CAS
Email: caoyong@siom.ac.cn