Erbium-Implanted WS₂ Flakes with Room-Temperature Photon Emission at Telecom Wavelengths

Area of Science:

• Quantum technologies
• Materials science
• Solid-state physics

Background:

• Optically addressable spin impurities in crystals are key for solid-state quantum technologies.
• Reconciling emitter and host material constraints is a major challenge.
• Rare-earth ions in two-dimensional (2D) materials offer a potential solution due to their atomic-like transitions and versatile van der Waals systems.

Purpose of the Study:

• To investigate the photon emission properties of Erbium (Er)-doped Tungsten Disulfide (WS2) flakes.
• To explore the potential of 2D materials as hosts for rare-earth quantum emitters.
• To assess the suitability of these systems for quantum technology applications.

Main Methods:

• Ion implantation of Erbium into WS2 flakes.
• Confocal microscopy for optical characterization.
• Ab initio calculations for theoretical analysis.
• Optical spectroscopy and polarization-selective measurements.

Main Results:

• Identified narrow, long-lived photoluminescence lines in the telecom band from Er-doped WS2.
• Activated these emission lines via low-temperature thermal annealing.
• Observed uniform spectral and polarization response across the ensemble of emitters.
• Demonstrated stable fluorescence brightness over a range of temperatures, indicating inefficient nonradiative relaxation.

Conclusions:

• Er-doped WS2 flakes provide a viable platform for 2D-hosted, telecom-band quantum emitters.
• The temperature stability and narrow linewidths are advantageous for quantum applications.
• This work opens avenues for novel solid-state devices integrating these emitters with photonic structures.