2016/05/31 by Marcelo Wu, Nathanael L. -Y. Wu, Nathanael L. Y. Wu +6 · 83 citations
Engineering · Physics and Astronomy · #Advanced MEMS and NEMS Technologies #Condensed matter physics #Force Microscopy Techniques and Applications #Magnetic field #Magnetic moment #Magnetization #Magnetometer #Materials science #Mechanical and Optical Resonators #Mesoscopic physics #Nanophotonics #Nanoscopic scale #Nanosensor #Nanotechnology #Optoelectronics #Permalloy #Physics #cond-mat.mes-hall #physics.optics
paper · pdf · doi:10.1038/nnano.2016.226
published in Nature Nanotechnology 12(2), 127-131 (Nature Portfolio) · 7 pages, 4 figures
openalex publication_date 2016/10/31 · arxiv created 2016/11/02 · arxiv updated 2016/11/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Nanophotonic optomechanical devices allow observation of nanoscale vibrations with sensitivity that has dramatically advanced metrology of nanomechanical structures [1-9] and has the potential to impact studies of nanoscale physical systems in a similar manner [10, 11]. Here we demonstrate this potential with a nanophotonic optomechanical torque magnetometer and radiofrequency (RF) magnetic susceptometer. Exquisite readout sensitivity provided by a nanocavity integrated within a torsional nanomechanical resonator enables observations of the unique net magnetization and RF-driven responses of single mesoscopic magnetic structures in ambient conditions. The magnetic moment resolution is sufficient for observation of Barkhausen steps in the magnetic hysteresis of a lithographically patterned permalloy island [12]. In addition, significantly enhanced RF susceptibility is found over narrow field ranges and attributed to thermally assisted driven hopping of a magnetic vortex core between neighboring pinning sites [13]. The on-chip magneto-susceptometer scheme offers a promising path to powerful integrated cavity optomechanical devices for quantitative characterization of magnetic micro- and nanosystems in science and technology.