Designing terahertz sensors for highly sensitive detection of nanoscale thin films and a few biomolecules poses a substantial challenge but is crucial for unlocking their full potential in scientific research and adva...Designing terahertz sensors for highly sensitive detection of nanoscale thin films and a few biomolecules poses a substantial challenge but is crucial for unlocking their full potential in scientific research and advanced applications.This work presents a strategy for optimizing metamaterial sensors in detecting small quantities of dielectric materi-als.The amount of frequency shift depends on intrinsic properties(electric field distribution,Q-factor,and mode volume)of the bare cavity as well as the overlap volume of its high-electric-field zone(s)and the analyte.Guided by the simplified dielectric perturbation theory,interdigitated electric split-ring resonators(ID-eSRRs)are devised to significantly enhance the detection sensitivity compared with eSRRs without interdigitated fingers.ID-eSRR’s fin-gers redistribute the electric field,creating strongly localized enhancements,which boost analyte interaction.The periodic change of the inherent antiphase electric field reduces radiation loss,leading to a higher Q-factor.Experiments with ID-eSRR sensors operating at around 300 GHz demonstrate a remarkable 33.5 GHz frequency shift upon depositing a 150 nm SiO_(2)layer as an analyte simulant,with a figure of merit improvement of over 50 times compared with structures without interdigitated fingers.This rational design offers a promising avenue for highly sensitive detection of thin films and trace biomolecules.展开更多
文摘Designing terahertz sensors for highly sensitive detection of nanoscale thin films and a few biomolecules poses a substantial challenge but is crucial for unlocking their full potential in scientific research and advanced applications.This work presents a strategy for optimizing metamaterial sensors in detecting small quantities of dielectric materi-als.The amount of frequency shift depends on intrinsic properties(electric field distribution,Q-factor,and mode volume)of the bare cavity as well as the overlap volume of its high-electric-field zone(s)and the analyte.Guided by the simplified dielectric perturbation theory,interdigitated electric split-ring resonators(ID-eSRRs)are devised to significantly enhance the detection sensitivity compared with eSRRs without interdigitated fingers.ID-eSRR’s fin-gers redistribute the electric field,creating strongly localized enhancements,which boost analyte interaction.The periodic change of the inherent antiphase electric field reduces radiation loss,leading to a higher Q-factor.Experiments with ID-eSRR sensors operating at around 300 GHz demonstrate a remarkable 33.5 GHz frequency shift upon depositing a 150 nm SiO_(2)layer as an analyte simulant,with a figure of merit improvement of over 50 times compared with structures without interdigitated fingers.This rational design offers a promising avenue for highly sensitive detection of thin films and trace biomolecules.
