Detection of ultralow magnetic field requires magnetic sensors with high sensitivity and low noise level,especially for low operating frequency applications.We investigated the transport properties of tunnel magnetore...Detection of ultralow magnetic field requires magnetic sensors with high sensitivity and low noise level,especially for low operating frequency applications.We investigated the transport properties of tunnel magnetoresistance(TMR)sensors based on the double indirect exchange coupling effect.The TMR ratio of about 150%was obtained in the magnetic tunnel junctions and linear response to an in-plane magnetic field was successfully achieved.A high sensitivity of 1.85%/Oe was achieved due to a designed soft pinned sensing layer of CoFeB/NiFe/Ru/IrMn.Furthermore,the voltage output sensitivity and the noise level of 10.7 mV/V/Oe,10 nT/Hz^(1/2)at 1 Hz and3.3 nT/Hz^(1/2)at 10 Hz were achieved in Full Wheatstone Bridge configuration.This kind of magnetic sensors can be used in the field of smart grid for current detection and sensing.展开更多
基金Supported by the Framework Project of SGCC(Grant No.5700-202058381A-0-0-00)the National Key Research and Development Program of China(Grant No.2017YFA0206200)。
文摘Detection of ultralow magnetic field requires magnetic sensors with high sensitivity and low noise level,especially for low operating frequency applications.We investigated the transport properties of tunnel magnetoresistance(TMR)sensors based on the double indirect exchange coupling effect.The TMR ratio of about 150%was obtained in the magnetic tunnel junctions and linear response to an in-plane magnetic field was successfully achieved.A high sensitivity of 1.85%/Oe was achieved due to a designed soft pinned sensing layer of CoFeB/NiFe/Ru/IrMn.Furthermore,the voltage output sensitivity and the noise level of 10.7 mV/V/Oe,10 nT/Hz^(1/2)at 1 Hz and3.3 nT/Hz^(1/2)at 10 Hz were achieved in Full Wheatstone Bridge configuration.This kind of magnetic sensors can be used in the field of smart grid for current detection and sensing.
