Plasmon-driven Ultrafast and Highly Efficient Saturable Absorption for Ultrashort Pulse Generation Based on 2D V2C

TL;DR

This paper demonstrates that few-layer V2C MXene, with its tailored surface plasmon resonance, acts as an efficient saturable absorber for ultrafast laser pulse generation at telecommunication wavelengths, combining experimental and theoretical insights.

Contribution

The study introduces V2C MXene as a novel plasmon-driven saturable absorber with ultrafast nonlinearities for the first time, enabling high-performance mode-locked lasers.

Findings

V2C exhibits a high saturable absorption coefficient of -1.35 cm/GW at 1550 nm.

Mode-locked laser pulses of 486 fs duration were generated at 1569 nm.

The device shows stable operation with a 92 dB SNR.

Abstract

Plasmon-driven ultrafast nonlinearities hold promise for advanced photonics but remain challenging to harness in two-dimensional materials at telecommunication wavelengths. Here, we demonstrate few-layer V2C MXene as a high-performance saturable absorber by leveraging its tailored surface plasmon resonance. Combining transient absorption spectroscopy and first-principles calculations, we unveil a plasmon-driven relaxation mechanism dominated by interfacial high-energy hot electron generation (~100 fs), enabling giant ultrafast nonlinearities. Crucially, at the communication band (1550 nm), V2C exhibits a high saturable absorption coefficient of -1.35 cm/GW. Integrating this into an erbium-doped fiber laser, we generate mode-locked pulses with a duration of 486 fs at 1569 nm, a 39.51 MHz repetition rate, and exceptional stability (92 dB SNR). This work establishes plasmonic MXenes as a paradigm for tailored ultrafast photonic devices.