Trion transfer in mixed-dimensional heterostructures

TL;DR

This paper demonstrates an efficient, doping-independent method for trion emission in heterostructures by transferring trions from 2D to 1D materials, significantly enhancing emission efficiency and expanding excitonic physics.

Contribution

It introduces a novel transfer mechanism for trions in mixed-dimensional heterostructures, bypassing doping requirements and overcoming Auger-quenching limitations.

Findings

Trion emission efficiency increased by over 100-fold.

Transfer process is robust across various doping conditions.

Extends exciton transfer paradigm to three-body quasiparticles.

Abstract

Charged excitons, or trions, offering unique spin and charge degrees of freedom, have primarily been investigated in doped systems where charges are long considered indispensable. Here, we present an alternative route to ultra-efficient trion emission from an intrinsic, defect-free semiconductor via a transfer mechanism. By exciting trions in two-dimensional tungsten-diselenide donors and transferring them into one-dimensional carbon-nanotube acceptors in mixed-dimensional heterostructures, we circumvent the usual carrier requirement, overcoming intrinsic Auger-quenching limitations. Benefitting from a reservoir effect induced by dimensional heterogeneity, this process achieves trion emission efficiencies increased by over 100-fold compared to conventional doping-based approaches, and remains robust across diverse doping conditions. Our findings extend the exciton transfer paradigm to the three-body quasiparticles, offering a new platform for advancing excitonic physics and trion-based optoelectronic/spintronic applications.