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The three-dimensional spin structure of the magnetic vortex of FeSiB, an amorphous soft magnetic material, was investigated by holography observation and computer simulation. Magnetization distribution in the neighborhood of the vortex center was estimated from the phase distribution obtained by holography observation. To confirm this magnetization distribution, sample-tilting experiments were performed: when the sample was tilted with respect to the electron beam direction, the phase-image center was found to shift along the tilting axis. Finite-element computer simulation was carried out to estimate the amount of shifts of the phase-image center in the sample tilting from the experimental magnetization distributions in the no sample-tilting conditions. We found that the simulated shifts of the phase-image center were in good agreement with those in the sample-tilting experiment, thus confirming the magnetization distribution near the vortex center obtained by holography observation. [ABSTRACT FROM PUBLISHER]

Three-dimensional (3D) reconstruction experiments were carried out by observing high-resolution 3D electrostatic potential distributions of Pt nanoparticles using off-axis electron holographic tomography. These Pt nanoparticles were mounted on the surfaces of amorphous silicon pillars. In order to realize high-resolution observation, we developed a mechanically stable 3D specimen holder with small specimen drifts and vibrations. From the 3D electrostatic potential distribution data of Pt nanoparticles (2.0 nm in diameter), we obtained the resolution of 1.5 nm. [ABSTRACT FROM PUBLISHER]

Observing and characterizing the spin distributions ona nanometer scale are of vital importance for understanding nanomagnetismand its application to spintronics. The magnetic structure in MnSithin samples prepared from a bulk, which undergoes a transition froma helix to a skyrmion lattice, was investigated by in situ observationusing Lorentz microscopy. Stripe domains were observed at zero appliedfield below 22.5 K. A skyrmion lattice with 6-fold symmetry in realspace appeared when a field of 0.18 T was applied normal to the filmplane. The lattice constant was estimated to be 18 nm, almost identicalto the helical period. In comparison with the marginally stable skyrmionphase in a bulk sample, the skyrmion phase was stable over a widerange of temperatures and magnetic fields in the thin samples. [ABSTRACT FROM AUTHOR]

The magnetic interaction between the pole tip of a single-pole head and a pseudo soft underlayer in perpendicular magnetic recording was observed by electron holography. The magnetic flux density inside the soft underlayer was quantitatively evaluated. The distribution of magnetic flux density was calculated using the finite element method, and the influences of the modulation of the reference wave and stray fields were investigated by comparison with experimental results. The flux density observed was found to be underestimated due to the modulation of the phase shift in reference wave. The magnetic flux measured experimentally was larger than that inside the specimen because of the relatively large stray fields above and below the specimen in the direction of the electron beam. [ABSTRACT FROM AUTHOR]

A newly developed 1 MV field‐emission transmission electron microscope has recently been applied to the field of superconductivity by utilizing its bright and monochromatic field‐emission electron beam. This microscope allows individual magnetic vortices inside high‐Tc superconductors to be observed, thus, opening the way to investigate the unusual behaviour of vortices, which reflects the anisotropic layered structure of these superconducting materials. One example is the observation of the arrangements of chain vortex lines that are formed when a magnetic field is applied obliquely to the layer plane of the materials. [ABSTRACT FROM PUBLISHER]

We developed a 1 MV field-emission transmission electron microscope. This paper reports details and specifications of the instrument. The microscope was designed to obtain a bright and coherent electron beam by using the field emission gun equipped with a pre-accelerating magnetic lens and the highvoltage power supply with high stability (0.5 ppm min−1). Using this microscope, the brightness of 1.8×1010 A cm−2 sr−1 and the lattice resolution of 49.8 pm were attained. [ABSTRACT FROM PUBLISHER]

Electron interference has been investigated at an industrial laboratory of Hitachi, Ltd. for the past 30 years thanks to the encouragement and support of C. N. Yang, who retired from the State University of New York in 1999. This paper reports here fundamentals and applications of electron interference experiments we have carried out including our relation to C. N. Yang, and is based on a talk made in honor of him at the "Symmetries and Reflections" Symposium held at Stony Brook in May 1999. [ABSTRACT FROM AUTHOR]

Unstained ferritin molecules were observed as a contour map of the phase of the transmitted electron wave for the first time, by means of phase-difference amplified holographic interference electron microscopy. In addition to the outer shapes of the ferritin cores, the surrounding protein layers 6 nm in thickness could also be recognized in these contour maps. [ABSTRACT FROM PUBLISHER]

The new technique of electron holography which has recently been put to practical use with a field-emission electron microscope is reviewed. Electron holography enables discernment of the electron phase, an aspect which has not been fully utilized so far in electron microscopy. Among several applications of electron holography, interference microscopy in particular was proven to be promising for practical purposes, since the contour fringes of the transmitted electron wavefront indicated the thickness contours of a homogeneous specimen and the magnetic lines of force of a ferromagnetic specimen. Further developments of electron holography technique are expected to open new possibilities of both observation and measurements in atomic dimensions. [ABSTRACT FROM PUBLISHER]

The magnetic flux distribution for fine iron particles less than 200 nm in size with the habit of rhombic dodecahedron is studied by high voltage electron microscopy and electron holography. It is concluded that a particle has a magnetic flux component rotated in a {110} plane and enclosed within it. The advantage of using high voltage electron microscopy for examining the magnetic structure is also discussed. [ABSTRACT FROM PUBLISHER]

A field emission electron microscope with highly stabilized gun and illuminating system was developed. Several experiments were made to demonstrate the high performance of the microscope. The brightness of the beam was more than that of the conventional ones, which feature was demonstrated by taking 300 Fresnel fringes and 3,000 bi-prism fringes. Furthermore, monochromatic feature of the microscope makes the effect of chromatic aberration smaller and the half-spacing fringes of nickel {220} planes (1/2 d=62Å) were observed. [ABSTRACT FROM PUBLISHER]