Effect of AlN Film on the Magnetic Properties of Rare Earth-Transition Metal Film

The amorphous TbFeCo films covered with the protective AIN films have been prepared by the rf magnetron sputtering system.It is found that the protective AIN films not only protect rare earth elements from oxidation and enhance magneto-optical Kerr effect but also affect the magnetic properties of the rare earth-transition metal films.The coercivity Hc and perpendicular magnetic anisotropy energy constants K'U1 and KU2 of the films are changed with the thickness of the protective AIN films.It can be explained according to the stress mechanism and the model of single ion anisotropy.

An Electrothermodynamic Analysis of the Field Evaporation in the Configuration of Scanning Tunneling Microscope

This paper presents an electrothermodynamic(Born-Haber-type)analysis of field evaporation in the configuration of scanning tunneling microscope,in which the adatom is only partially ionized and evaporated to counter electrode.As a result a formula was derived,which employed a so-called effective binding energy Aeff.The calculated evaporation field for Au-1,at a tip-sample distance of d=7.23Åand an evaporation rate of 10^(11)s^(-1),is 0.6 V/Å,which agrees well with Chang's experiment[Phys.Rev.Lett.72(1994)574].

Improvement of Magnetoresistive Character of NiO/NiFeCo/Cu/NiFeCo Exchange-Biased Spin-Valves Through Annealing in Magnetic Field

NiO(70 nm)/NiFeCo(5 nm)/Cu(2 nm)/NiFeCo(5 nm)spin-valve multilayers were prepared by electron beam evaporation.It is found that the magnetoresistive(MR)ratio of the as-deposited films is relatively small(about 1.6%)and there is no apparent biasing in MR curves of as-deposited multilayers due to weak exchange coupling.Through heat treatment at a proper temperature in a magnetic field,the exchange field of the materials increases and the multilayers show good exchange-biased spin-valve MR character with MR value reaching about 2.5%.The proper temperature range for annealing is 200-250℃.With further increasing temperature,MR ratio drops rapidly.

Optical and Electric and Structural Properties of Ti_(1-x)Al_(x)N Thin Films

A sequence of Ti_(1-x)Al_(x)N films has been prepared by rf reactive magnetron sputtering.The optical and electric properties versus aluminum content x have been studied.Values suitable for magneto-optic protective layers have been achieved in Ti_(1-x)Al_(x) N thin films with aluminum content x>0.75.X-ray diffraction results show that Ti_(1-x)Al_(x) N thin films in this study are a bcc structure up to x=0.75,further increase in the aluminum content gives a wurtzite structure.All of the results show that the optical and electric properties of Ti_(1-x)Al_(x) N films might be related to the crystal structure.

Investigation of Niobium(Nb)Substitution on Structural and Superconducting Properties of(Bi,Pb)-Based Superconductors

In this study, the effects of Nb substitution on the Bi-based superconducting materials have been investigated. The X-ray diffraction measurement indicated coexistence of Bi-2212, Bi-2223 phases and some impurity phases of CuO, CuNb2O6, CaNb2O6, CaCuO2, and Sr5Nb5O16. With increasing Nb content, impurity phases consistent with the Nb element appeared in the samples. Also with increasing Nb content, the Bi-2223 phase of samples gradually was decreased and in contrast, the Bi-2212 phase was increased. From the SEM, results have been seen that with increasing of Nb contents, the crystal structure of the samples was slightly changed because of the disrupted grain growth. From the electrical resistivity measurements, it has been found that with increasing of Nb contents, critical temperature decreases and the superconducting transition width (ΔT) increases. Estimated critical current density showed that Jc decreases with increasing Nb content, as expected.

FMR of Multi-layered Magnetic Film LaYIG/GGG/LaYIG/GGG

1 Introduction Since single crystal magnetic films which have multiple layers with the same magnetization such as LaYIG/GGG/LaYIG film were first made by the authors, they have been widely used in microwave delay line with linear dispersion and other devices. Recently ferromagnetic resonance （FMR） and magnetostatic wave propagation characteristics of similar multi-layered film have been studied by many authors, whichris important for the multi-layered film to be used in microwave region. But until now many important characteristics of the multi-layered film have not been well understood. The direction and magnitude of uniaxial anisotropy effective field H11, the widening of FMR linewidth △H,

Fatigue characteristics of ferroelectric (Pb_(0.925)La_(0.075))-(Zr_(0.65)Ti_(0.35))_(0.981)O_3 thin films

Due to the applications in electronics and optics in the past two decades, ferroelectricthin films (BaTiO3, PbTiO3, (Pb1-xLax)(ZryTi1-y)O3（PLZT x/y/1-y）, LiNbO3, Bi4Ti3O12,etc.)have been widely investigated. Especially, ferroelectric thin film memory, combining the ad-vantage of semiconductor memory with that of magnetic memory, has properties including highspeed, high density, nonvolatility and good radiation hardness, and can be compatible

Study on Ferroelectric PLZT Thin Films Prepared by rf Magnetron Sputtering

Due to many particular characteristics of ferroelectric thin films, such as ferroelectric switching characteristics, piezoelectric effect, pyroelectric effect,electrooptic and sound-optic effect, nonlinear optics effect, etc., ferroelectric thin films have wide applications in microelectronics and optocelectronics. Especially success in ferroelectric memory based on ferroelectric thin films, which show good properties