A5081335327- Magnetic properties of thin films
- Magnetic Properties and Applications
- Adhesion, Friction, and Surface Interactions
- Atmospheric aerosols and clouds
- Nuclear Physics and Applications
- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Physics of Superconductivity and Magnetism
- Meteorological Phenomena and Simulations
- Nuclear reactor physics and engineering
- Climate variability and models
- Metal and Thin Film Mechanics
- Theoretical and Computational Physics
- Magnetic Bearings and Levitation Dynamics
- Copper Interconnects and Reliability
- Nuclear physics research studies
- Metallic Glasses and Amorphous Alloys
- Magnetic Properties of Alloys
- Phase-change materials and chalcogenides
- Particle accelerators and beam dynamics
- Atmospheric and Environmental Gas Dynamics
- Magnetic and transport properties of perovskites and related materials
- Atomic and Subatomic Physics Research
- Precipitation Measurement and Analysis
- Surface Roughness and Optical Measurements
National Defense Academy of Japan
2012-2025
Tohoku University
1991-2008
National Defence Academy
2007-2008
Japan Agency for Marine-Earth Science and Technology
2005-2006
Tohoku Institute of Technology
1996-2005
Institute for Global Environmental Strategies
2003-2004
Akita Industrial Technology Center
1994-2003
Takushoku University
2003
Kobe University
1999-2001
University of Toyama
1982
By the analysis of self-consistent magnetization and direct observation remanent a real tape, authors discussed obstacles which are, will be, encountered in attaining higher recording densities with present magnetic system, uses mainly longitudinal mode. Then properties three modes (longitudinal, circular, perpendicular) are compared. The mode transformation is also discussed. Finally new perpendicular system proposed for high density recording. And some results fundamental experiments...
For a new perpendicular magnetic recording system, Co-Cr film with anisotropy has been developed by an RF sputtering. The films are found to show some suitable properties for high density such as anisotropy, rectangular M-H loop, and fine grain structure. An extremely of 100,000 bits/inch was realized using the film. crystal microscopic structure also discussed, is mainly originated from uniaxial magneto-crystalline anisotropy.
This paper describes the recent studies for magnetic head, medium and recording properties on a new perpendicular system. The complemental features between longitudinal are discussed to establish an efficient Superior response in amplitude peak shift characteristics digital signal proves that magnetization mode is basically free from demagnetization high densities maximum density has been limited merely by resolution of reproducing head. Significant improvement sensitivities head made using...
For a recently proposed perpendicular recording system, composite anisotropy medium has been developed to improve the sensitivity of head. The is composed Fe-Ni soft magnetic film and Co-Cr film, which are successively deposited on base by an r. f. sputtering. By using new double layer medium, extremely high could be obtained, compared with single medium. current needed saturate decreased one-tenth that for film. Although was material, neither deterioration frequency response nor peak shift...
Since perpendicular magnetic recording is free from demagnetization, high-density up to the intrinsic limit of a medium possible. This prediction was verified experimentally in flexible disk system using single-pole head and Co-Cr/Ni-Fe double-layer medium. We could record reproduce signals 680KFRPI. The bit length at highest density order Co-Cr columnar diameter.
The extremely high resolution properties in a perpendicular magnetic recording system were studied with recently developed Co-Cr film medium. Bitter technique was used to observe magnetization distribution the medium, and transition of directly observed on top bottom surfaces film. It proved that an ideal mode, having very narrow width, takes place even density over 40 kBPI. From angular variation H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML"...
It has been deduced from the analysis of recording demagnetization mechanism in magnetic that short wavelengths remanent magnetization exhibits a closed-loop structure medium. In this paper novel experimental method is presented to confirm existence such (a circular mode) and investigate its for usual medium heads. The transformation mode perpendicular also discussed.
The demagnetization effect in magnetic recording must be evaluated, not as static self-demagnetization, but a dynamic demagnetizing field at an instant when the head is applied to medium. From this fact it becomes necessary obtain self-consistent magnetization distribution A method of calculation and its results are described. relation between longitudinal vector clarified. experimental sinusoidal pulse width peak shift digital interpreted new phenomena that related dynamical behavior process.
This paper reviews research results for the head, medium and recording properties of a perpendicular system. Superior bit density characteristics obtained so far indicate that is basically free from demagnetization in high region it will establish new field technology future. The prediction explained context complementary profiles longitudinal recording. At very beginning magnetic recording, perpendicular-type head was considered but abandoned because suitable did not exist. Progress...
Here we present extensive observations of stratospheric and upper tropospheric water vapor using the balloon‐borne Cryogenic Frost point Hygrometer (CFH) in support Aura Microwave Limb Sounder (MLS) satellite instrument. Coincident measurements were used for validation MLS version 1.5 a limited 2.2 vapor. The sensitivity is on average 30% lower than that CFH, which fully compensated by constant offset at levels but only partially levels, leading to an dry bias. may be adjusted correlation...
A polarization lidar was continuously operated aboard the research vessel Mirai in tropical western Pacific over three northern winters: at 2.0°N, 138.0°E during November and December 2001; 138.5°E 2002; 7.5°N, 134.0°E 2004 January 2005. Intensive radiosonde soundings were made from 3‐h intervals all campaigns. The mechanisms that underlie observed variations cirrus tropopause layer (TTL) are discussed viewpoint of large‐scale dynamics transport. During 2001 campaign, region cold, but TTL...
In a perpendicular recording system, Co-Cr film as medium is capable of storing very high density signals. Lorentz microscopy 1000 kV TEM was used to observe the structure recorded magnetizations in films having anisotropy. A composite with soft magnetic back layer shown by have horseshoe magnetization structure. The stable antiparallel transition determined head-on layer, which consists new straw-rope domain found consist small domains magnetized through thickness correspond columnar...
We investigated water vapor variations in the tropical lower stratosphere on seasonal, quasi‐biennial oscillation (QBO), and decadal time scales using balloon‐borne cryogenic frost point hygrometer data taken between 1993 2009 during various campaigns including Central Equatorial Pacific Experiment (March 1993), once or twice annually Soundings of Ozone Water Region (SOWER) project eastern (1998–2003) western Southeast Asia (2001–2009), Ticosonde regular sounding at Costa Rica (2005–2009)....
We develop a new forward algorithm for the retrieval of effective size and ice water content (IWC) crystals in clouds by using collocated 95‐GHz (3.16 mm) cloud radar lidar with wavelength 0.532 μm. Use or alone has fundamental difficulty to obtain microphysics because wide variety distributions particles, though it is macrophysical information such as boundaries. The combined use can overcome this problem. One unique feature attenuation‐correction signals according determined look‐up tables...
Design consideration of double-layered perpendicular magnetic recording media for ultrahigh-density was studied based on a micromagnetic model. It found that the introduction an appropriate exchange coupling between grains remarkably improves resolution media. The essential role could be understood it increases M-H loop slope, which has same contribution to as head field gradient. Large values product slope parameter and gradient are expected result in small transition widths less than 10...
We show characteristics of a tropical deep convection observed in an experiment employing the A‐train constellation, spaceborne imager Moderate Resolution Imaging Spectroradiometer (MODIS), sounder Atmospheric Infrared Sounder (AIRS)‐advanced microwave sounding unit (AMSU), cloud radar CloudSat, and lidar Cloud‐Aerosol Lidar with Orthogonal Polarisation (CALIOP). CloudSat CALIOP measured vertical cross section at 1.1 km from its center, where center is defined as local minimum brightness...
Recent advances in the Co-Cr media are discussed regarding their potential recording and physical properties. The head reproducing resolution is most important for high density perpendicular recording. medium, if it has a fine columnar structure, shows very resolution, since columns predicted to show rotational mode of magnetization reversal, also offer an ideal mode. Stress placed on remaining issues : improvement reliability through improvements durability ; supply quality base materials.
Double layered media for perpendicular magnetic recording were made by dc magnetron sputtering. The coercivity of the Co-Cr layer was independent deposition rate over range from 0.006 to 1.2 μm/min, when substrate temperature kept constant during Micro columnar structure film studied chemical etching. Only columns dissolved leaving column boundaries showing a microhoneycomb structure. From composition analysis etchant, Cr segregated confirmed exist even in high sputtered films. Permalloy...
From the measurements of surface field a recording medium, it was obtained that an almost ideal step change distribution magnetization is formed in perpendicular for digital signals. The fact represents upper limit usable density determined only by resolution reproducing head. Therefore, reproduction head successfully analyzed using reciprocity theorem. By introducing thickness loss main pole head, satisfactory coincidence between calculated and measured results wavelength response even at...
The magnetic field distribution of the perpendicular recording head has been investigate using a large scale model. This paper discusses actual from measured results in model head. It is shown that strength increases and becomes very sharp because interaction between medium. which consists having anisotropy medium demagnetization-free high densities.
Abstract This paper describes a novel use of A‐Train observations to estimate vertical velocities for actively growing convective plumes and relate them cloud internal structure. Convective velocity is derived from time‐delayed (1–2 min) IR measurements MODIS IIR. are found be clustered around 2–4 m/s but the distributions positively skewed with long tails extending larger values. Land convection during 13:30 overpasses has higher than those 1:30 overpasses; oceanic shows opposite, albeit...
A simple magnetic transition model is proposed for perpendicular recording with a single-pole head. It has been found that the amplitude of transitions proportional to coercivity H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</inf> medium and independent saturation magnetization M xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> if <tex xmlns:xlink="http://www.w3.org/1999/xlink">M_{s} \gsim (3/4\pi) H_{c}</tex> . Experimental proof using...
The feasibility of high track density recording in a perpendicular magnetic system has been investigated. properties the field single pole type (SPT) head having narrow width were studied by using large scale model and medium. y-field gradient SPT near edge is steeper than x-field ring head, it was confirmed Bitter technique that recorded acculately coincides with main head. Perpendicular also superior off-track characteristics crosstalk signal hardly detected even at very pitches. From...
Abstract. A meteorological balloon-borne cloud sensor called the particle (CPS) has been developed. The CPS is equipped with a diode laser at ∼ 790 nm and two photodetectors, polarization plate in front of one detectors, to count number particles per second obtain cloud-phase information (i.e. liquid, ice, or mixed). lower detection limit for size was evaluated laboratory experiments as 2 µm diameter water droplets. For current model output voltage often saturates droplets equal greater than...