半円型ブルズアイ構造を有する直列型ナノメカニカル振動子によるＱ値非依存波長計測

抄録

Optomechanical nanoresonators, which consist plasmonic structures and nanomechanical resonators, have been studied for the wavelength measurement. By plasmonic structures, the light absorption rate is dependent on the wavelength. The absorbed light changes into heat and applies thermal stress to the resonator. And the thermal stress can be measured as the resonant frequency shift. In this method, Q factor decides the detection resolution but Q factor decreases by heat absorption. In this study, we used nanomechanical resonators elastically coupled in series. The resonators enable Q factor independent measurement using the amplitude change of antisymmetric vibration mode by applied thermal stress. And we used half bull's-eye structures as plasmonic structures. The structures absorb light with a specific wavelength and conduct light to the resonators. We demonstrated nanomechanical resonators elastically coupled in series and half bull's eye structures can achieve Q factor independent wavelength measurement and the minimum detection resolution was 338 pm.