Abstract

A minimal theory is presented for nonradiative energy transfer from a two-dimensional exciton, especially a moiré-localized exciton, to a nearby graphene layer. The transfer rate is written as an overlap between the exciton near-field spectrum and the long-wavelength electronic loss function of graphene, weighted by an exciton form factor. The framework reproduces the z^-4 point-dipole limit and shows that finite exciton localization filters high-momentum components, making photoluminescence quenching a probe of localization length. A Pauli-blocking model predicts recovery of PL intensity and lifetime as 2|mu_F| approaches hbar omega. The minimal model is benchmarked against the full random-phase-approximation loss function of doped graphene and applied to TMDC/hBN/graphene heterostructures.

Abstract

A minimal theory is presented for nonradiative energy transfer from a two-dimensional exciton, especially a moiré-localized exciton, to a nearby graphene layer. The transfer rate is written as an overlap between the exciton near-field spectrum and the long-wavelength electronic loss function of graphene, weighted by an exciton form factor. The framework reproduces the z^-4 point-dipole limit and shows that finite exciton localization filters high-momentum components, making photoluminescence quenching a probe of localization length. A Pauli-blocking model predicts recovery of PL intensity and lifetime as 2|mu_F| approaches hbar omega. The minimal model is benchmarked against the full random-phase-approximation loss function of doped graphene and applied to TMDC/hBN/graphene heterostructures.

Abstract

A minimal theory is presented for nonradiative energy transfer from a two-dimensional exciton, especially a moiré-localized exciton, to a nearby graphene layer. The transfer rate is written as an overlap between the exciton near-field spectrum and the long-wavelength electronic loss function of graphene, weighted by an exciton form factor. The framework reproduces the z^-4 point-dipole limit and shows that finite exciton localization filters high-momentum components, making photoluminescence quenching a probe of localization length. A Pauli-blocking model predicts recovery of PL intensity and lifetime as 2|mu_F| approaches hbar omega. The minimal model is benchmarked against the full random-phase-approximation loss function of doped graphene and applied to TMDC/hBN/graphene heterostructures.

Abstract

A minimal theory is presented for nonradiative energy transfer from a two-dimensional exciton, especially a moiré-localized exciton, to a nearby graphene layer. The transfer rate is written as an overlap between the exciton near-field spectrum and the long-wavelength electronic loss function of graphene, weighted by an exciton form factor. The framework reproduces the z^-4 point-dipole limit and shows that finite exciton localization filters high-momentum components, making photoluminescence quenching a probe of localization length. A Pauli-blocking model predicts recovery of PL intensity and lifetime as 2|mu_F| approaches hbar omega. The minimal model is benchmarked against the full random-phase-approximation loss function of doped graphene and applied to TMDC/hBN/graphene heterostructures.