Demagnetization Effect in a Meander-Core Orthogonal Fluxgate Sensor

Demagnetization effect plays an important role in the magnetic core design of the orthogonal fluxgate sensor. In this paper, a meander-core orthogonal fluxgate sensor based on amorphous ribbon is described. The demagnetization model of meander-core structures is established, and the average demagnetization factor can be evaluated by finite element modeling. Simulation and experimental analyses were performed to study the effects of demagnetization on the sensitivity and linear range of orthogonal fluxgate sensors in the fundamental mode by varying the number of strips, the line width, and the spacing of the meander-cores. The results were compared and revealed a very close match. The results show that the demagnetization factor increases with an increase in the number of strips and the line width, which leads to an increase in the linear range of the sensors. The sensitivity can be improved by increasing the number of strips appropriately, however, it is reduced when the line width increases. Smaller spacing results in a larger demagnetization factor due to the magnetic interactions between adjacent strips, which reduces the sensitivity of the sensor. The results obtained here from simulations and experiments are useful for designing magnetic sensors with similar structures.

Anisotropy of Lower Critical Field in Organic Layered Superconductor λ-(BETS)2GaCl4

The lower critical field of type-II organic layered superconductor l-(BETS)2GaCl4 has been estimated by magnetic measurements. The demagnetization factor of a needle-like sample shape has been taken into account for the measurements by applying the external field, parallel and perpendicular to the conducting plane. The lower critical field for the field parallel to the conducting plane is 5.5(2) G, in contrast with the previous studies. This allows us to discuss the anisotropy of lower critical field Hc1 in a quasi-two-dimensional organic layered superconductor l-(BETS)2GaCl4.

Lower Critical Field of Layered Organic Superconductor with Asymmetrical Donor κ-(MDT-TTF)2AuI2

We report magnetization measurement in the superconducting state of a type-II organic layered superconductor with asymmetrical donor k-(MDT-TTF)2AuI2. The demagnetization factor of a plate-like shape of the single crystal has been taken into account for the measurement by applying an external field perpendicular to the conducting plane. The superconducting transition temperature TC is determined to be 4.7 K through the detection of demagnetization signal. The lower critical field is 10.5±1.4 G. This result implies that the stable vortex state of k-(MDT-TTF)2AuI2 can be reached at the applied magnetic field above 105 Oe

Modeling the effect of the stress demagnetization phenomenon on the magnetic properties in a no Fe-Si 3% sheet

The aim of this paper is the modeling of the stress demagnetization effect on the magnetic properties in a non-oriented Fe-Si 3% sheet under different external stresses. The magneto-mechanical model used for magnetic hysteresis is based on a model originally formulated by Sablik-Jiles-Atherthon (S.J.A.). This latter has been modified by including both the stress demagnetization factor and the eddy current effects. The influence of the stress demagnetization term SDT on the magnetostrictive behavior of the material is also modeled. The proposed model has been validated by extensive simulations at different stresses, namely compressive and tensile stresses. Simulation results obtained by this model are very close to those published in the literature. Using the proposed model, very satisfactory performance has been achieved.