Submicron ultraviolet single-mode microlaser enabled by electrical pumping

Abstract

Electrically pumped single-mode micrometer/submicrometer lasers, are promising for optical interconnects, data communications, biosensing, optical 3D facial recognition, and other fields. Generally, reducing the cavity size for expanding the free spectral range is the most direct and effective approach to constructing single-mode lasers. However, current research primarily focuses on achieving this through optical pumping, due to the inadequate electrical and optical properties of low-dimensional semiconductors. Herein, a stable room-temperature whispering-gallery-mode microlaser diode driven by electricity is developed, integrating the grown indium-doped ZnO submicrometer-wire (ZnO:In SMW) as the gain medium. Under electrical pumping conditions, the diode enables lasing in the ultraviolet spectral region at ∼382.8 nm, accompanied by the effective suppression of spontaneous radiation. Specifically, capitalizing on the exceptional quality laser gain material and well-designed device architecture, it exhibits fascinating characteristics, including a high quality (Q)-factor (∼2552), a low-threshold current (∼10.5 mA), and robust single-frequency lasing operation. This work paves a pathway for the advancement of single-mode miniaturized lasers with electrical stimulation.