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Previously we reported the dynamics of an isolated straight domain wall near the compensation point in amorphous GdCo and GdCoAu films prepared by rf-sputtering. Nonlinear dependence of the wall velocity on drive field is observed. Here we describe the effects of externally applied in-plane field and in-plane anisotropy of the film on domain wall dynamics in amorphous GdCo magnetic films. The wall whose plane is perpendicular to the in-plane easy axis shows higher velocity and smaller wall motion coercive force compared with the wall whose plane is parallel to the in-plane easy axis. The domain wall velocity depends on the directions of pulse magnetic field and external in-plane field. The effects of external in-plane field in low field region are different from those in high field region.

TbFe films were applied as media in magnetic printing. Magnetic domains which were produced thermomagnetically with laser beam scanning were developed with toner particles and these images were transferred to papers. 2 μm thick TbFe films with perpendicular anisotropy yields a resolution of 15 line/mm when a He-Ne laser beam (13mW) focussed to 2 μm in diameter was used to produce latent magnetic images. Printed images with gray tone could be obtained macroscopically by controlling the width and the line density of the reversed domains thermomagnetically written. TbFe films were proved to be useful for magnetic printing.

Some results of the magneto-optical effect spectra of rare-earth-transition-metal amorphous films are presented. These results suggest that the polarity reversal of the Kerr hysteresis loops on the surface of the films after annealing with limited oxidation is sometimes not due to the magnetic origin but may be mainly due to the change of the optical properties of the oxide surface layer.

The magnetic properties of multilayered films consisting of an amorphous Gd-Co layer having a uniaxial magnetic anisotropy perpendicular to the film plane, and a Permalloy or a Tb-Fe layer having an in-plane anisotropy are studied. The thickness dependence of the shift of compensation temperature is studied in the amorphous Gd-Co film coated with Permalloy. When the Permalloy film is thicker than 600A, the shift of compensation temperature becomes constant (about 5°C). Above a thickness of 2500A of the amorphous Gd-Co film, the shift of compensation temperature becomes constant ( about 5°C). On the other hand, if the amorphous Gd-Co film is 1500A thick, the change of compensation temperature does not occur. In the multilayered film having a nonmagnetic layer between the amorphous Gd-Co and the Permalloy film, no shift of compensation temperature occurs. The magnetic properties of thin Tb-Fe films coated on amorphous Gd-Co films have also been studied. When the thickness of the Tb-Fe is greater than about 100A and thinner than about 500A, the polarity of the Kerr hysteresis loops in double layered films changes.

Amorphous TbFeCo films have been studied to obtain a higher Kerr rotation angle. The Kerr rotation of Tb 21 (Fe 100-x Co x ) 79 increases with the increase of Co concentration and has a maximum value of 0.52 degree at X=50, 840nm and decreases in X > 50. This Kerr rotation angle of 0. 52 degree is improved by a factor of 2. 5 compared to that of Tb Fe. In amorphous Tb 21 (Fe 100-x Co x ) 79 film, the wavelength dependence of Kerr rotation angle were measured from 500nm to 840nm. Kerr roation increases monotonically with the increase of wavelength and no peak was observed in spectra. However, it was found that there was an obvious difference of the increase rate of 8k, from 500nm to 840nm, between the R-Co alloy system and the R-Fe alloy system. The increase of Kerr rotation angle depends on the difference of the contribution of pure Fe and Co to 8k.

Amorphous Sm-Co magnetic films have been obtained by magnetron sputtering for studying the temperature dependences of electrical and magnetic properties. Films prepared by this method exhibit a uniaxial anisotropy in the film plane. The temperature dependence of electrical resistivity in amorphous Sm-Co films with composition from 10 to 40 at.% Sm has been investigated. The temperature range is from 4.2 K to 300 K. Films sputtered with bias voltage in an applied magnetic field normal to the substrate have a normal (perpendicular) component of magnetization. Polar Kerr hysteresis loops were measured through the glass substrate at temperatures between 230 K and 370 K. Magnetic hysteresis loops were also measured by vibrating sample magnetometer at temperatures between 77 K and 300 K. The temperature dependence of coercivity in Sm 30 Co 70 and Sm 20 Co 80 films has been investigated.

The Kerr rotation angle θk of Tb21(Fe100-XCoX)79 increases from 0.18° to 0.36° with increasing Co content X from 0 to 15. On the other hand, θk of (Tb21Fe79)100-XCrX reduced with increasing X. The Curie temperature of Tb21(Fe100-XCoX)79 and (Tb21Fe79)100-XCrX rose with increasing Co and Cr concentration.

Some results are shown in this paper about stripe domain control in magnetic garnet films which have been studied as a laser beam deflector. A wide control range of the stripe domain period is achieved using (BiNdYb) 3 Fe 5 O 12 garnet film. In this film, the magnetization inclines slightly from the film plane, and when the stripe domain is employed as a grating, the deflection angle of its first order diffraction beam changes about 20 degrees with an in-plane field of 400 Oe. On the other hand, in a YIG-coated (YSmLuCa) 3 (FeGe) 5 O 12 garnet film, regular parallel stripe domains nucleate in any orientation homogeneously.

Heat‐treatment effects on the saturation magnetization Ms, the coercivity Hc, and the perpendicular anisotropy Ku of CoCr films with rather low Hc were investigated. Heat treatment up to 450 °C caused interdiffusion of Co and Cr atoms in a compositionally modulated film, resulting in reduction of Ms. On the other hand, heat treatment at 500 °C increased Ms, Hc, and Ku, which was interpreted to be the segregation of nonmagnetic alloy. Measurement of the temperature dependence of Ms supported this interpretation. Heat treatment at 500 °C seemed to have the similar effect on microstructure in a film to substrate heating during deposition. From Ku‐Ms curves, the packing density of the ferromagnetic region in heat‐treated films was estimated to be 77% of that in as‐sputtered ones.

The electrical resistivity and the galvanomagnetic effect in Gd-Co sputtered films were studied as a function of temperature between 1.5 and 390 K. The logarithmic temperature dependence of electrical resistivity was dominant in the region from 1.5 to 35 K and disappeared after crystallization. The quadratic temperature dependence of electrical resistivity was observed from 50 to 390 K together with the resistivity minimum. The temperature dependence of transverse magnetoresistivity was measured to investigate the effect of magnetic domain walls to the temperature dependence of electrical resistivity. The temperature dependence of transverse magnetoresistivity was about one hundredth as large as that of electrical resistivity.

We have investigated the dynamics of an isolated straight domain wall near the compensation temperature in rare-earth transition metal amorphous magnetic films. Wall velocities up to 3.5 × 104cm/sec are observed for applied field up to 550 Oe. Nonlinear dependence of the wall velocity on drive field is observed. The wall mobility in low drive region is very sensitive to the temperature and/or to the coercive force of the film. In high drive region, remarkable transient behavior, that is, very high instantaneous velocity just after the onset of wall motion and velocity break down are detected. Some films have remarkable orthorhombic anisotropy, and in these films the domain wall velocity depends on the direction of the wall motion with respect to the in-plane easy axis of the film. Change of the wall velocity by Permalloy overlay is also observed.

A magnetic garnet film was studied as a leakage flux sensor for detecting defects in a steel surface. The modification of magnetization in the garnet film by the leakage was detected magnetooptically. The perpendicular anisotropy of the garnet film is sensitive only to the normal component of the stray field. The spatial resolution of the measurement was high as a result of the small effective lateral dimensions of the film, as determined by the size of the light beam (as small as 10 mu m in the present experiment). A leakage field profile from an artificial groove in a magnetized steel was therefore measurable with high accuracy. Although the sensitivity and the spatial resolution with which defects were detected decreased when the effective film area was enlarged by increasing the spacing between the film and the defect, the groove width was evaluated with an accuracy better than 15 mu m. >

Magnetic anisotropy in sputter‐deposited SmxCo100−x amorphous films depended on the substrate temperature even for a narrow composition range of 18≤x≤26. Deposition between 90 and 140 °C brought a negative perpendicular anisotropy. All the films were magnetically isotropic in the film plane with zero torque curve for a field rotated in the film plane, suggesting that the negative perpendicular anisotropy did not come from easy axes of uniaxial anisotropy due to some structures being in the film plane. A large negative anisotropy vanished after annealing. On the other hand, a positive anisotropy which overcomes the demagnetizing energy was induced by a deposition at 60–90 °C. Films with a positive perpendicular anisotropy had a relatively large electric resistivity and hence a large Hall resistivity. The magnetostriction measurement showed that a stress (film/substrate)‐induced anisotropy did not play an important role in both positive and negative perpendicular anisotropies. A possible origin of the large...

The Kerr rotation angle has been measured at λ = 6328A, for the Co-Cr films (0-29.5at%Cr). The films were deposited by magnetron rf sputtering on glass substrates. Over the range of 18- 29.5at%Cr, the deposited films were found to have perpendicular anisotropy, the Kerr rotation angles in the saturated state were 6-0.3 minutes, and the reflectivities were 63-58%. The Kerr rotation angle of the Co-Cr films was attributed to the magnetic moment of Co. The external field dependence of the Kerr rotation angle had a hysteresis with a large coercive force and remanence, in comparison with those obtained by magnetic measurement, indicating that the coercivity near the film surface is larger than that of inside. The Kerr hysteresis loop can be measured and is useful to estimate the magnetic properties of Co-Cr films. It can be applied not only to the single Co-Cr films but to the double-layer films. The domain pattern of recorded signal on Co-Cr film can be observed by a microscope using the polar Kerr magnetooptic effect.

Thermomagnetic writing utilizing temperature dependence of coercivity was proposed in magneto-optical recording as high density thin film memory. Rare earth-transition metal(RE-TM) amorphous films with perpendicular magnetization(GdFe,GdCo,TbFe etc.) were successfully prepared by sputtering or evaporation technique. Multi-source rf-sputtering method was used to prepare a uniform amorphous film. Uniformity of compensation temperature, Curie temperature and coercivity over a wide area was fairly good under the insertion of the window. Amorphous TbFeCo,GdFeBi and GdCoBi films have been studied to obtain a higher Kerr rotation angle that is important characteristic of magneto-optic recording media.

The magnetic properties of ferrimagnetic amorphous films (Gd-Co, Gd-Co-Au) with perpendicular anisotropy, coated with Permalloy films with the in-plane anisotropy, have been investigated. Coating with Permalloy film or transition metal films (Fe, Ni, Co) lowers the compensation temperature in the amorphous films about 5°C compared with that of single layer. Therefore, the coercive force of the amorphous film coated with a transition metal film differs from that of single layer. On the other hand, coating with rare-earth metal film (Gd) or non-magnetic film (Ag) does not cause a shift of the compensation temperature. The direction of nucleated stripe domains in the amorphous films of double layers is controlled by a low in-plane field (15 Oe).

X-ray photoelectron studies on amorphous TbFeCo ternary alloy films prepared by rf-sputtering, with several bias voltages, have been made under UHV conditions. The XPS binding energies were identical to those of the pure elements and the alloy within the experimental accuracy. The Fe XPS spectra of amorphous TbFeCo films increased and approximated to the Fe XPS spectrum of FeCo binary alloy film with increasing a bias voltage. The Co XPS spectra of amorphous TbFeCo films, however, were independent of the increase of bias voltage. It was found that, in amorphous TbFeCo film with the same composition, the film prepared under a higher bias voltage had a larger Kerr rotation angle. It was concluded that the state change of Fe in amorphous TbFeCo film caused the difference of Kerr rotation angle.

In this paper, indications of pacemaking and its results are discussed form 24 cases of servere bradyarrhythmias with Stokes-Adams syndorme experienced from October 1966 to March 1972. There are no mortality and 87.5% Of all returned to social activity. Postimplantation complications, including pacemaker malfunctions, electrode feilure and abnormally electrical findings during pacing are investigated.

Pulsed Doppler flowmetry has proved to be very sensitive and specific in the diagnosis of intracardiac regurgitation. However, conventional pulsed Doppler flowmeters are to some extent limited in the evaluation of regurgitant flow. In order to accurately and extensively examine regurgitant flow, it would be necessary to locate a sampling site where blood flow is being measured, on a two-dimensional cardiac image. Furthermore, it would be very benefitial to measure intracardiac flow simultaneously at multiple sites along the Doppler beam. For these reasons, we have newly developed a computer-based multigated pulsed Doppler flowmeter combined with an electronic beam sector scanning echocardiograph.

The temperature dependences of the extraordinary Hall effect (EHE) and the polar Kerr effect (PKE) hysteresis loops are measured in amorphous rare‐earth (RE) transition metal (TM) films. The polarity of each effect corresponds to that of its TM component. The temperature dependence of Hall voltage is similar to that of the Kerr rotation angle, and, in Gd‐Co‐Mo films, it is similar to that of Co sublattice moment calculated by Hasegawa's two sublattice model. From these results, both EHE and PKE in RE‐TM films are considered to mainly associate with the TM sublattice moment.

The detection of flow disturbances in the heart and great vessels by pulsed Doppler echocardiography has great potentials in the noninvasive assessment of valvular and shunt disease (1,2). Recent investigations (3-5) have suggested that the extent or the area of the flow disturbances may reflect the severity of the valvular abnormalities. Current advent of real-time, two-dimensional duplex Doppler echocardiography has provided a more exact localization of the sample volume in the heart and great vessels, and enabled us to evaluate the extent of the flow disturbances very accurately. However, it is sometimes difficult to determine the presence or absence of the flow disturbance from a representation of the audio spectrum, the time interval histogram, since this analysis is easily modified by improper setting and is sensitive to noise and signal amplitude. Although the multifilter soundspectrogram could express all information available in the pulsed Doppler signal, it is also qualitative. Thus, recent interest has focused on Fourier analysis as a possible method of quantitating flow disturbances from Doppler signals (7–10).

Three cases of the single atrium (cor triloculare biventricularis) were operated upon successfully, and diagnostic and surgical aspects of this rare malformation were discussed.

Two cases of the common atrium associated with persistent left superior vena cava directly connecting into the left side of the atrium are reported. In both patients, the mitral cleft was repaired and the atrial septum was newly constructed with a large teflon-patch. The left superior vena cava was ligated in Case 1, and in Case 2 a tunnel to transfer the emptying orifice of the left superior vena cava to the right side of the atrium was made from a pericardial pedicle. The former was reoperated upon due to the severe residual mitral insufficiency but died after mitral valve replacement. The latter was discharged with a good condition.

We have studied the effects of Bi-doping on the perpendicular anisotropy in sputtered Gd(Fe1-x Co x ) amorphous films. Over the range of 0 ≦x ≦1, the perpendicular anisotropy increases remarkably with the addition of Bi-atoms together with the shift of saturation magnetization toward the transition metal TM dominant magnetically. GdFe films doped with Bi have a perpendicular anisotropy even when prepared under a bias-potential application. The increase of anisotropy by Bi-doping is interpreted neither by the term of a stress nor by a simple shape anisotropy. It is considered that the segregation of non-ferromagnetic GdBi x , takes place. The alignment of the TM dominant phase in the region of GdBi x would be the origin of a large perpendicular anisotropy.

It is very difficult to prepare Sm–Co ferromagnetic film with perpendicular anisotropy, though RE–TM ferrimagnetic films with perpendicular anisotropy are well prepared (RE: rare earth, TM: transition metal). Because of the exceptional magnetic properties of Sm–Co magnetic film as magnetic recording media, we studied to prepare Sm–Co magnetic film with perpendicular magnetization. Films were deposited by a magnetron RF sputtering onto glass substrates (T sub=80∼-100°C) and with a bias voltage (V b=-60∼-80 V). The magnetic hysteresis loops, polar Kerr hysteresis loops and torque curves of this film are characterized by a uniaxial perpendicular anisotropy.

The remanence of amorphous TbFe films with perpendicular anisotropy deposited by several deposition methods was investigated. The uniaxial anisotropy was enhanced in films deposited onto rotating substrates. The coercivity increased with dual gun sputtering compared to single gun sputtering. The remanence did not depend on the anisotropy directly but was mainly related to the wall coercivity. In dual gun rf magnetron sputter-deposited films onto rotating substrates, the wall coercivity was so large that magnetization rotation dominated the magnetization reversal, resulting in high remanence. The wall coercivity also increased in laminated films. A high remanence of 300 Gs with a residual ratio of 1 has been obtained in Tb31Fe69 films produced with a repetition of the deposition of a 0.5 µm thick lamina and the time intervals between the sputtering of each lamina.

Rare earth transition metal amorphous magnetic thin films with a uniaxial magnetic anisotropy normal to the film plane may be used in memory devices in the future. The magnetic properties are required to be uniform for such an application. This paper describes experimental results on the uniformity of Gd-Fe thin films prepared by various deposition methods and proposes a new deposition method, electron beam deposition through a specially-shaped window onto a revolving substrate. Use of a revolving substrate produces uniformity of the magnetic properties in amorphous thin films, but has direct effects upon the internal structure of such films.

The magnetic properties of double-layered amorphous GdCo film consisting of films with different compensation temperatures were studied. The theoretical hysteresis loops and their temperature dependence were deduced using the double-layer model. It was confirmed that the magnetic properties of the double-layered amorphous GdCo film agreed well with the prediction by the double-layer model. From the temperature dependence of the double-layered film, it is shown that an apparent compensation temperature exists between the original compensation temperatures in each layer. The appearance of the inverted loop is explained using the double-layer model; this was confirmed by experiments in the double-layered amorphous GdCo film.

This paper describes a new type of optical processing based on the dynamic scattering effect in liquid crystals. It is possible to realize a binary spatial filter with nematic liquid crystals and to control the optical modes by voltage signals. A two-dimensional Walsh function is used for extracting properties of the input patterns. The realization of an 8 x 8 Walsh function filter with nematic liquid crystals is demonstrated. The contrast ratio is over 30 to 1. The variation in transparency is within +/-3%. Experimental results show that it is possible to extract the properties of handwritten characters by detecting the intensity of light transmitted through both the input pattern and the liquid crystal filter.

A transducer for compressive force using Mn-Mg and Ni-Zn ferrite is offered in this paper, based on the magnetomechanical effect that the magnetic characteristics of the material are influenced by mechanical stress. They can be realized by applying a Royer's and Marzolf's circuit. The input to the transducer is pressure, and the output is an oscillator frequency. The change of the magnetic characteristics caused by repeated application and removal of 1.8 kg/mm2pressure can be reversible. With a Marzolf type transducer, at low pressure the input-output characteristic shows a hysteresis till 0.9 kg/mm2, but at higher pressure than 0.9 kg/mm2the characteristics are completely linear. With a Royer type transducer the characteristics are almost linear, although a little hysteresis is found over the range from 0 to 1.8 kg/mm2. The experimental results show that at low pressure the characteristics are nonlinear, including the hysteresis, and the influence of the temperature is 1.2%/°C over the range from 18 to 30°C. The method is also useful in the case of investigating the flux reversal mechanism under various stress conditions.