Microwave FRET imaging inside a photonic cavity
Light can be trapped inside a cavity made by two mirrors, thus concentrating the light intensity and enhancing interactions between light and matter. Among the different applications of these photonic cavities, much attention is now focused on their ability to control the energy exchange between quantum emitters such as atoms, molecules, and quantum dots. Attempts to improve this exchange have been hampered by experimental difficulties in controlling the positions, orientations, and spectra of the emitter’s dipoles. In a recent paper published in Phys Rev X, we thoroughly characterize dipole-dipole energy transfer inside a photonic cavity and provide design rules for cavity-enhanced applications.
While previous research has focused on optical frequencies, microwave experiments allow us to measure energy transfer with a high degree of control over dipole orientation and position. We test our framework by investigating the energy transfer between two microwave antennas inside a photonic cavity and derive the conditions that enhance the transfer.
Our methodology bridges the gap between quantum electrodynamics and microwave engineering descriptions of dipole-dipole interactions. Beyond the conceptual interest, this approach provides a practical tool to quantitatively characterize photonic devices with an enhanced dipole-dipole interaction and can be readily applied to map energy transfer inside complex photonic systems at ultrahigh resolutions.