A big enough transverse magnetic field applied to soft magnetic ferrite toroid can magnetize the ferrite to a saturation level in transverse direction and almost completely suppresses magnetic domain structures in the...A big enough transverse magnetic field applied to soft magnetic ferrite toroid can magnetize the ferrite to a saturation level in transverse direction and almost completely suppresses magnetic domain structures in the ferrite,the response to the longitudinal alternating electromagnetic field changes from the original domain wall displacements and spin rotations to the precession of magnetization around the transverse field,and the hysteresis loss disappears in the ferrites.Both theoretical and experimental results indicate that the permeability and magnetic loss in the ferrite can be controlled by adjusting the transverse magnetic field.A higher Q value with relatively low permeability can be achieved by increasing the transverse field,which ensures that the ferrite can be operated at high frequencies,with magnetic loss being very low.展开更多
The magnetic phase diagram of rare-earth perovskite compound,GdScO3,has been investigated by magnetization and heat capacity.The system undergoes an antiferromagnetic phase transition at TN=2.6 K,with an easy axis of ...The magnetic phase diagram of rare-earth perovskite compound,GdScO3,has been investigated by magnetization and heat capacity.The system undergoes an antiferromagnetic phase transition at TN=2.6 K,with an easy axis of magnetization along the a axis.The magnetization measurements show that it exists a spin-flop transition around 0.3 T for the applied field along the a axis.The critical magnetic field for the antiferromagnetic-to-paramagnetic transition is near 3.2 T when temperature approaches zero.By scaling susceptibilities,we presume this point(B=3.2 T,T=0 K)might be a fieldinduced quantum critical point and the magnetic critical fluctuations can even be felt above TN.展开更多
The barocaloric effect(BCE)is a promising alternative to traditional vapor compressing refrigeration because of its environmentally friendly impact and high energy efficiency.However,the driving hydrostatic pressure f...The barocaloric effect(BCE)is a promising alternative to traditional vapor compressing refrigeration because of its environmentally friendly impact and high energy efficiency.However,the driving hydrostatic pressure for most BCE materials is relatively high,which is not conducive to practical application.In this paper,we report that the large barocaloric entropy change of MnAs_(0.94)Sb_(0.06)alloy can be induced by low hydrostatic pressures.Its phase transition temperature is strongly sensitive to the applied pressure,resulting in a large barocaloric coefficient of 134 K·GPa^(-1)on cooling and 126 K·GPa^(-1)on heating.The maximum barocaloric entropy change and adiabatic temperaturechange resulted from hydrostatic pressure of 40 MPa reach up to 26.3 J·kg^(-1)·K^(-1)and 14.4 K,respectively,showing an excellent barocaloric performance.The results demonstrate that the MnAs_(0.94)Sb_(0.06)alloy is a promising alternative for BCE refrigeration.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2022YFB3504800 and 2021YFB3502400)the Key Research and Development Plan of Anhui Province,China(Grant No.202003c08020012)the Key Program of Education Department of Anhui Province,China(Grant No.KJ2019ZD03)。
文摘A big enough transverse magnetic field applied to soft magnetic ferrite toroid can magnetize the ferrite to a saturation level in transverse direction and almost completely suppresses magnetic domain structures in the ferrite,the response to the longitudinal alternating electromagnetic field changes from the original domain wall displacements and spin rotations to the precession of magnetization around the transverse field,and the hysteresis loss disappears in the ferrites.Both theoretical and experimental results indicate that the permeability and magnetic loss in the ferrite can be controlled by adjusting the transverse magnetic field.A higher Q value with relatively low permeability can be achieved by increasing the transverse field,which ensures that the ferrite can be operated at high frequencies,with magnetic loss being very low.
基金The work at SUSTech was supported by the National Natural Science Foundation of China(Grant No.11974157)Part of this work was also supported by the National Natural Science Foundation of China(Grant No.11875265)+1 种基金the Scientific Instrument Developing Project of the Chinese Academy of Sciences(3He-based neutron polarization devices)the Institute of High Energy Physics,the Chinese Academy of Sciences.Kan X C and Tian M L were supported by the National Natural Science Foundation of China(Grant No.51802002).
文摘The magnetic phase diagram of rare-earth perovskite compound,GdScO3,has been investigated by magnetization and heat capacity.The system undergoes an antiferromagnetic phase transition at TN=2.6 K,with an easy axis of magnetization along the a axis.The magnetization measurements show that it exists a spin-flop transition around 0.3 T for the applied field along the a axis.The critical magnetic field for the antiferromagnetic-to-paramagnetic transition is near 3.2 T when temperature approaches zero.By scaling susceptibilities,we presume this point(B=3.2 T,T=0 K)might be a fieldinduced quantum critical point and the magnetic critical fluctuations can even be felt above TN.
基金financially supported by the National Natural Science Foundation of China (No.U22A20117)the National Natural Science Foundation of China (No.52271175)。
文摘The barocaloric effect(BCE)is a promising alternative to traditional vapor compressing refrigeration because of its environmentally friendly impact and high energy efficiency.However,the driving hydrostatic pressure for most BCE materials is relatively high,which is not conducive to practical application.In this paper,we report that the large barocaloric entropy change of MnAs_(0.94)Sb_(0.06)alloy can be induced by low hydrostatic pressures.Its phase transition temperature is strongly sensitive to the applied pressure,resulting in a large barocaloric coefficient of 134 K·GPa^(-1)on cooling and 126 K·GPa^(-1)on heating.The maximum barocaloric entropy change and adiabatic temperaturechange resulted from hydrostatic pressure of 40 MPa reach up to 26.3 J·kg^(-1)·K^(-1)and 14.4 K,respectively,showing an excellent barocaloric performance.The results demonstrate that the MnAs_(0.94)Sb_(0.06)alloy is a promising alternative for BCE refrigeration.
