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Abstract: During June to October 2000 and 2001 we measured the height, Diameter at Breast Height (DBH) and stand density of Betula ermanii trees at Mt. Mae-Shirane, Japan and the [...]

CO adsorbed layer of Pt(111) electrode undergoes reconstruction when exposed to UV-irradiation (266 nm) from a nanosecond or femtosecond laser. UV induce CO desorption and retrapping cycles, which passed through electronic excited states at the surface were sustained on the electrode surface.

We present results of a time-resolved study of the ultrafast magnetic response of [Gd.sub.23.1] [Fe.sub.71.9] [Co.sub.5.0] magnetically amplified magnetooptical systems (MAMMOS) structures under conditions near actual read/write temperatures. An all-optical pump and probe method was used in which an intense (pump) light beam excited a medium due to ultrafast laser heating and a less intense (probe) beam monitored this photo-excited state through the magnetooptical Kerr effect. Our experiment clearly demonstrates that the photo-excitation effectively excites coherent spin waves in the magnetic material. Precession frequencies of several gigahertz and relaxation times in the nanosecond range were observed. Index Terms--Magnetization precession, MAMMOS, thermomagnetic writing.

For higher density MO recording, a magnetic domain expansion readout method named MAMMOS has been proposed [1]. Herein we report a novel MAMMOS scheme using an in-plane to perpendicular magnetization changing effect. Expansion readout has been achieved by both a magnetic field modulation method and a light intensity modulation method. A clearly amplified readout signal was reproduced from repetition of 0.2 [Mu] m packed marks.

The MAMMOS (magnetic amplifying magneto-optical system) read-out is achieved by applying an alternating external magnetic field for domain expansion and collapse processes. Since the read-out magnetic domain size is expanded by a magnetic field, a strong enhancement in the amplitude of the read-out signal is expected. The read-out laser power dependence of the MAMMOS signal was measured, and the resolution was estimated empirically. Applying an alternating magnetic field with suitable intensity, MAMMOS readout was realized for a certain range of read-out laser power. The resolution and the margin of magnetic field depended on the laser power. Even at a 0.2 [[micro]meter] domain size, its signal was recognizable without interference at the optimum laser power. A C/N level of over 50 dB was obtained for a 0.2 [[micro]meter] domain size. Index terms - CNR, domain expansion, magneto-optical disk, resolution.

Magnetic Multi-Valued (MMV) recording process is studied by numerical simulation including thermomagnetic effect. A medium, which consists of PtCo capping layer coupled to TbFeCo recording layer, switches the signal of Kerr rotation angle responding to the external field in four levels. The time evolution of generated pattern of recording mark is calculated by extending the previous magneto-optical (MO) recording simulation for single layer system.

New magnetic configurations in 2D and 3D artificial lattices are studied by solving the non-linear equation based on the classical Heisenberg models for 2D and 3D artificial lattices. The results indicate strong possibility to be used as an ultra-high density magnetic recording media achieved by magnetic multi-valued (MMV) recording. The MMV states are based on the magnetic anisotropic configurations in 2D and 3D artificial lattices. In this paper, the magnetic properties of these artificial lattices and the density of MMV recording are discussed.

Presents a study that described a method for the measurement of coercive force in magnetic bubble garnets using microwave absorption. Analysis of the derivative absorption signal as a function of bias field; Examination of the derivative absorption as a function of modulation field amplitude; Application of the method on several bubble garnets.