Erbium-implanted WS2 flakes with room-temperature photon emission at telecom wavelengths

TL;DR

This study demonstrates Erbium-doped WS2 flakes as stable, room-temperature telecom-band photon emitters, combining experimental and computational methods to advance solid-state quantum device integration.

Contribution

It introduces a novel approach using ion implantation and spectroscopy to create and analyze Er-doped 2D materials with telecom-band emission at room temperature.

Findings

Narrow, long-lived emission lines in the telecom band

Uniform optical response across the ensemble

Brightness unaffected by temperature changes

Abstract

Optically addressable spin impurities in crystals along with device engineering provide an attractive route to realizing quantum technologies in the solid state, but reconciling disparate emitter and host material constraints for a given target application is often challenging. Rare-earth ions in two-dimensional (2D) materials could mitigate this problem given the atomic-like transitions of the emitters and the versatile nature of van der Waals systems. Here we combine ion implantation, confocal microscopy, and ab-initio calculations to examine the photon emission of Er-doped WS2 flakes. Optical spectroscopy reveals narrow, long-lived photo-luminescence lines in the telecom band, which we activate after low-temperature thermal annealing. Spectroscopic and polarization-selective measurements show a uniform response across the ensemble, while the fluorescence brightness remains mostly unchanged with temperature, suggesting non-radiative relaxation channels are inefficient. Our results create opportunities for novel solid state devices coupling 2D-hosted, telecom-band emitters to photonic heterostructures separately optimized for photon manipulation.