Stimulated emission at 1.54 $\mu$m from Erbium/Oxygen-doped silicon-based light emitting diodes

TL;DR

This paper demonstrates room-temperature stimulated emission at 1.54 μm from Er/O-doped silicon LEDs with a low threshold, achieved through a novel deep cooling process, advancing silicon photonics for optical communication.

Contribution

It introduces a new deep cooling technique enabling stimulated emission in Er/O-doped silicon LEDs at room temperature, overcoming previous efficiency limitations.

Findings

Stimulated emission achieved at 1.54 μm with low threshold current.

Deep cooling creates a donor band facilitating emission.

Carrier transfer involves relaxation from silicon's indirect conduction band.

Abstract

Silicon-based light sources including light-emitting diodes (LEDs) and laser diodes (LDs) for information transmission are urgently needed for developing monolithic integrated silicon photonics. Silicon doped by ion implantation with erbium ions (Er$^{3+}$) is considered a promising approach, but suffers from an extremely low quantum efficiency. Here we report an electrically pumped superlinear emission at 1.54 $\mu$m from Er/O-doped silicon planar LEDs, which are produced by applying a new deep cooling process. Stimulated emission at room temperature is realized with a low threshold current of ~6 mA (~0.8 A/cm2). Time-resolved photoluminescence and photocurrent results disclose the complex carrier transfer dynamics from the silicon to Er3+ by relaxing electrons from the indirect conduction band of the silicon. This picture differs from the frequently-assumed energy transfer by electron-hole pair recombination of the silicon host. Moreover, the amplified emission from the LEDs is likely due to a quasi-continuous Er/O-related donor band created by the deep cooling technique. This work paves a way for fabricating superluminescent diodes or efficient LDs at communication wavelengths based on rare-earth doped silicon.