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Sensitivity enhancement in magnetic sensor using CoFeB/Y₃Fe₅O₁₂ resonator.

ABSTRACT: Magnonics, an emerging research field that uses the quanta of spin waves as data carriers, has a potential to dominate the post-CMOS era owing to its intrinsic property of ultra-low power operation. Spin waves can be manipulated by a wide range of parameters; thus, they are suitable for sensing applications in a wide range of physical fields. In this study, we designed a highly sensitive, simple structure, and ultra-low power magnetic sensor using a simple CoFeB/Y₃Fe₅O₁₂ bilayer structure. We demonstrated that the CoFeB/Y₃Fe₅O₁₂ bilayer structure can create a sharp rejection band in its spin-wave transmission spectra. The lowest point of this strong rejection band allows the detection of a small frequency shift owing to the external magnetic field variation. Experimental observations revealed that such a bilayer magnetic sensor exhibits 20 MHz frequency shifts upon the application of an external magnetic field of 0.5 mT. Considering the lowest full width half maximum, which is about 2 MHz, a sensitivity of 10^-2 mT order can be experimentally achieved. Furthermore, the higher sensitivity in the order of 10^-6 T (µT) has been demonstrated using the sharp edge of the rejection band of the CoFeB/Y₃Fe₅O₁₂ bilayer device. A Y-shaped spin waves interference device with two input arms consisting of CoFeB/Y₃Fe₅O₁₂ and Y₃Fe₅O₁₂ has been theoretically investigated. We proposed that such a structure can demonstrate a magnetic sensitivity in the range of [Formula: see text] T (nT) at room temperature. The sensitivity of the sensor can be further enhanced by tuning the width of the CoFeB metal stripe.

SUBMITTER: Sarker MS

PROVIDER: S-EPMC9247025 | biostudies-literature |

REPOSITORIES: biostudies-literature

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