Focusing the electromagnetic field to 10^-6λ for ultra-high enhancement of field-matter interaction.

ABSTRACT: Focusing electromagnetic field to enhance the interaction with matter has been promoting researches and applications of nano electronics and photonics. Usually, the evanescent-wave coupling is adopted in various nano structures and materials to confine the electromagnetic field into a subwavelength space. Here, based on the direct coupling with confined electron oscillations in a nanowire, we demonstrate a tight localization of microwave field down to 10^-6λ. A hybrid nanowire-bowtie antenna is further designed to focus the free-space microwave to this deep-subwavelength space. Detected by the nitrogen vacancy center in diamond, the field intensity and microwave-spin interaction strength are enhanced by 2.0 × 10⁸ and 1.4 × 10⁴ times, respectively. Such a high concentration of microwave field will further promote integrated quantum information processing, sensing and microwave photonics in a nanoscale system.

SUBMITTER: Chen XD 

PROVIDER: S-EPMC8569218 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature