Aim to detect the characteristic weak magnetic field signal against the strong noises background. Methods In combination with a low-pass-filter, the correlation output of magne-* tic sensors between the magnetic field...Aim to detect the characteristic weak magnetic field signal against the strong noises background. Methods In combination with a low-pass-filter, the correlation output of magne-* tic sensors between the magnetic field and reference current was utilized to provide a DC output voltage proportional to the applied magnetic induction, computer simulation was* done to investigate the correlation output of the Hall-effect sensors. Results Some analysis results concerning the noise property, harmonic supppression and the sensitivity were given. Conclsion The minimum detection signal of the equipment evolved from the mentioned cor-* relation theory can be 10-6 T. In addition to the DC output, such sensors can also measure the phase of the detected magnetic induction and has good harmonic suppression as well as* noise elimination.展开更多
The phenomenon of EME and charge accumulation were included during the load-bearing failure processing of the rock.The mechanism and signal law of the two kinds of phenomenon through the experiment,as well as the mutu...The phenomenon of EME and charge accumulation were included during the load-bearing failure processing of the rock.The mechanism and signal law of the two kinds of phenomenon through the experiment,as well as the mutual relation of the two kinds of phenomenon,were contribute to monitor the regulation of the mine rock and pre- vent the dynamic disasters of the mine.There were two charge sensors,one electromag- netic radiated sensors and one pressure sensor in the experiment to detect the EME sig- nal and the charge intensity signal during the load-bearing failure processing of the rock. The results show that the charge intensity signal is prior to the EME signal through the date processing and numerical analysis.The two signals change obviously before the rock crush.The two kinds of phenomenon are homogenous and have obvious master-slave characteristic.With the appeared of the EME signal,the charge intensity signal decreased, the power is released.展开更多
A three-layer waveguide structure sensor consists of LHMs （left-handed materials） film surrounded by dielectric cladding and antiferromagnetie substrate is proposed. LHMs known as MTMs （metamaterials） have simulta...A three-layer waveguide structure sensor consists of LHMs （left-handed materials） film surrounded by dielectric cladding and antiferromagnetie substrate is proposed. LHMs known as MTMs （metamaterials） have simultaneous negative permeability and permittivity. The dispersion relation for the structure is derived for TE guided modes. Two ranges of frequencies are chosen such that Voigt permeability,μv, either negative or positive. The sensitivity is proven to be affected by different parameters including the film thickness, LHM parameters, and Voigt frequency.展开更多
This article describes in detail a technique for model!ng cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanica...This article describes in detail a technique for model!ng cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanical eigenmodes of the system. The force on each oscillator can then be determined from an overlap integral between magnetostrictive stress and the corresponding eigenmode, with the optomechanical coupling strength determining the ultimate resolution with which this force can be detected. Furthermore, an optomechanical magnetic field sensor is compared to other magnetic field sensors in terms of sensitivity and potential for miniaturization. It is shown that an optomechanical sensor can potentially outperform state-of-the-art magnetometers of similar size, in particular other sensors based on a magnetostrictive mechanism.展开更多
文摘Aim to detect the characteristic weak magnetic field signal against the strong noises background. Methods In combination with a low-pass-filter, the correlation output of magne-* tic sensors between the magnetic field and reference current was utilized to provide a DC output voltage proportional to the applied magnetic induction, computer simulation was* done to investigate the correlation output of the Hall-effect sensors. Results Some analysis results concerning the noise property, harmonic supppression and the sensitivity were given. Conclsion The minimum detection signal of the equipment evolved from the mentioned cor-* relation theory can be 10-6 T. In addition to the DC output, such sensors can also measure the phase of the detected magnetic induction and has good harmonic suppression as well as* noise elimination.
基金the National Natural Science Foundation of China(50490275)Education Office of Liaoning Province(20082123)
文摘The phenomenon of EME and charge accumulation were included during the load-bearing failure processing of the rock.The mechanism and signal law of the two kinds of phenomenon through the experiment,as well as the mutual relation of the two kinds of phenomenon,were contribute to monitor the regulation of the mine rock and pre- vent the dynamic disasters of the mine.There were two charge sensors,one electromag- netic radiated sensors and one pressure sensor in the experiment to detect the EME sig- nal and the charge intensity signal during the load-bearing failure processing of the rock. The results show that the charge intensity signal is prior to the EME signal through the date processing and numerical analysis.The two signals change obviously before the rock crush.The two kinds of phenomenon are homogenous and have obvious master-slave characteristic.With the appeared of the EME signal,the charge intensity signal decreased, the power is released.
文摘A three-layer waveguide structure sensor consists of LHMs （left-handed materials） film surrounded by dielectric cladding and antiferromagnetie substrate is proposed. LHMs known as MTMs （metamaterials） have simultaneous negative permeability and permittivity. The dispersion relation for the structure is derived for TE guided modes. Two ranges of frequencies are chosen such that Voigt permeability,μv, either negative or positive. The sensitivity is proven to be affected by different parameters including the film thickness, LHM parameters, and Voigt frequency.
文摘This article describes in detail a technique for model!ng cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanical eigenmodes of the system. The force on each oscillator can then be determined from an overlap integral between magnetostrictive stress and the corresponding eigenmode, with the optomechanical coupling strength determining the ultimate resolution with which this force can be detected. Furthermore, an optomechanical magnetic field sensor is compared to other magnetic field sensors in terms of sensitivity and potential for miniaturization. It is shown that an optomechanical sensor can potentially outperform state-of-the-art magnetometers of similar size, in particular other sensors based on a magnetostrictive mechanism.
