Ultrabroadband and sensitive cavity optomechanical magnetometry  

作　　者：Bei-Bei Li George Brawley Hamish Greenall Stefan Forstner Eoin Sheridan Halina Rubinsztein-Dunlop Warwick P.Bowen 

机构地区：[1]Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [2]School of Mathematics and Physics,The University of Queensland,St Lucia,QLD 4072,Australia

出　　处：《Photonics Research》2020年第7期1064-1071,共8页光子学研究（英文版）

基　　金：Defense Advanced Research Projects Agency(Qu ASAR Program);Australian Research Council(DP140100734,FT140100650);Defence Science and Technology Group(CERA49,CERA50);University of Queensland(2014001447)。

摘　　要：Magnetostrictive optomechanical cavities provide a new optical readout approach to room-temperature magnetometry.Here we report ultrasensitive and ultrahigh bandwidth cavity optomechanical magnetometers constructed by embedding a grain of the magnetostrictive material Terfenol-D within a high quality(Q)optical microcavity on a silicon chip.By engineering their physical structure,we achieve a peak sensitivity of26 p T∕Hz1/2 p comparable to the best cryogenic microscale magnetometers,along with a 3 d B bandwidth as high as 11.3 MHz.Two classes of magnetic response are observed,which we postulate arise from the crystallinity of the Terfenol-D.This allows single crystalline and polycrystalline grains to be distinguished at the level of a single particle.Our results may enable applications such as lab-on-chip nuclear magnetic spectroscopy and magnetic navigation.

关 键 词：CAVITY MAGNETOMETER MAGNETO 

分 类 号：TM936[电气工程—电力电子与电力传动]