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arXiv · 2503.06081

Optical Visualization of Carrier Surfing in 2D Monolayers Driven by Surface Acoustic Waves

Xueqian Sun·Shuyao Qiu·Hao Qin·Yuerui Lu
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Abstract

Charge carrier transport is pivotal in advancing nanoelectronics. Despite progress in exciton transport within ultra-thin semiconductors, the intertwined transport of free carriers and excitons presents challenges. Surface Acoustic Waves (SAWs) offer a compelling solution, enabling remote, real-time control of excitonic states at room temperature via surfing carriers in 2D materials, a relatively unexplored domain. SAWs create a versatile platform for tailoring excitonic states from microwave to optical frequencies. This study first demonstrates a simple route to visualize directional light transport and carriers drift driven by non-perfect Rayleigh-SAWs. We observed a maximum drift velocity of ~16.4 um/s for ionized carriers with SAW, significantly surpassing their natural movement in monolayers, though free electrons drift remains in the order of ~103 m/s. Enhanced exciton emission was achieved through standing SAWs, generating periodic oscillations. By combining traveling and standing wave portions, controllable, on-demand single-chip emission is feasible. Our findings open avenues for light manipulation, photonic circuits, and on-chip communications technologies.

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Xueqian Sun, Shuyao Qiu, Hao Qin, Yuerui Lu. 2025-03-08. Optical Visualization of Carrier Surfing in 2D Monolayers Driven by Surface Acoustic Waves. https://arxiv.org/abs/2503.06081

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