1530 nm Electroluminescence\nfrom Metal–Semiconductor–Metal\nStructured Devices Based on Oxygen–Erbium Co-doped MoS<sub>2</sub>

The 1530 nm emission of the Er intra-4f transition (<sup>4</sup>I<sub>13/2</sub> → <sup>4</sup>I<sub>15/2</sub>) is\nessential\nfor telecom communication because it corresponds to the minimum-loss\nwindow of silica optical fibers. Herein, we develop a metal–semiconductor–metal\nstructured light source based on O–Er co-doped MoS<sub>2</sub>. The electroluminescence device exhibits the 1530 nm emission at\nlow drive voltages (<5 V), which is beneficial from the impact\nexcitation with the space–charge-limited conduction mechanism.\nThe characteristic of symmetric structure allows the devices to exhibit\nconsistent electrical and electroluminescence performance at positive\nand negative voltages. The O doping contributes to such high-current\nelectrical behavior, and the Er doping leads to increased trap-filled-limited\nvoltage due to increased trap density. This work lays the foundation\nfor developing near-infrared light sources constructed with two-dimensional\nmaterials.