Continuous and Reversible Electrical Tuning of Fluorescent Decay Rate via Fano Resonance

TL;DR

This paper demonstrates electrical control over fluorescent decay rates using Fano resonance, enabling dynamic tuning of quantum emission properties for advanced photonic applications.

Contribution

The authors introduce a method to electrically tune fluorescent decay rates via Fano resonance by shifting a quantum object’s level spacing, affecting local density of states.

Findings

Decay rates can be tuned by up to two orders of magnitude.

Electrical shifting of quantum object’s level controls decay rates.

Potential applications include quantum technologies and spectroscopy.

Abstract

We demonstrate that the decay rates of a fluorescent molecule can be controlled by electrically shifting a transparency introduced by a Fano resonance. An auxiliary quantum object (QO), located at the hotspot of a plasmonic nanoparticle, suppresses plasmonic excitation at its level spacing {\omega}_QO. As a result, the local density of states (LDOS) associated with the plasmonic spectrum is also suppressed at {\omega}={\omega}_QO. By shifting {\omega}_QO via an applied voltage, we continuously tune the radiative and nonradiative decay rates of the fluorescent molecule by up to two orders of magnitude. This mechanism offers a valuable tool for integrated quantum technologies, enabling on-demand entanglement and single-photon sources, voltage-controlled quantum gate operations, and electrical control of superradiant-like phase transitions. The approach also holds promise for applications in super-resolution microscopy and surface-enhanced Raman spectroscopy (SERS).