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Notes: In order to develop a method to detect low-level oxygen in thin silicon crystals by photoluminescence (PL), a radiative carbon–oxygen center (C center: 0.79 eV) is formed in silicon crystals through carbon introduction by ion implantation. The PL intensity of the C center of the implanted sample is significantly increased by annealing the sample at 1000 °C followed by electron irradiation. The possibility of detecting a low concentration of oxygen (below 1×1015 atoms/cm3) in a layer thinner than 1 μm thick is seen. © 1995 American Institute of Physics.

Notes: Intercellular lipids of the stratum corneum contribute threefold to the maintenance of a healthy skin: by hydration, cell adhesion, and reduction of transepidermal water loss. All of these functions can be attributed to the self-organizing property of the amphiphilic molecules of the stratum corneum lipids. A new type of skin care product called Lamellar Gel was developed, which contains a (synthesized) pseudo-ceramide. Its structure is similar to that of ceramide found among the stratum corneum lipids, which allows it to control intramolecular interactions. Compared to regular emulsions the Lamellar Gel demonstrated better skin care characteristics regarding permeability, skin hydration, and skin occlusion. This was attributed to the fact that it formed the same self-organizing structure as natural stratum corneum lipids, hence showing a high affinity to the skin. A high moisturizing effect was observed as the Lamellar Gel combines the benefits of both O/W and W/O emulsions: it provides the same initial hydration as an O/W emulsion and at the same time the same occlusivity as a W/O emulsion. Transepidermal water loss increases under dry environmental conditions. This especially affects the skin around the eyes, where the skin is very thin, and wrinkles are very easily formed. Treatment with the Lamellar Gel recovered these wrinkles promptly and hydrated the stratum corneum for a long time.〈section xml:id="abs1-1"〉〈title type="main"〉ResumeLes lipides intercellulaires de l'epiderme contribuent trois fois au maintien de la sante de la peau: par l'hydratation, l'adhesion cellulaire, et la reduction de la perte d'eau transepidermique. Toutes ces functions peuvent etre attribuees la propriete d'auto-organisation des molecules amphiphiles des lipides de l'epiderme.On a developpe un nouveau type de produit de soin pour la peau, appele le Gel Lamellaire, qui contient un pseudo-ceramide (synthetique). Sa structure est similaire celle du ceramide present dans les lipides de l'epiderme, ce qui lui permet de controler les interactions intramoleculaires.Par rapport aux emulsions classiques le Gel Lamellaire a montre de meilleures proprietes de soin pour la peau vis--vis de la permeabilite, l'hydratation et le recouvrement de la peau. Ceci est attribue au fait qu'il forme la meme structure auto-organisante que les lipides de l'epiderme naturel, presentant pa la une forte affinite avec la peau. Un effet fortement hydratant a ete observe puisque le Gel Lamellaire associe les avantages des emulsions H/E et E/H: il apporte la meme hydratation initiale qu'une emulsion H/E et en meme temps le meme recouvrement qu'une emulsion E/H.La perte d'eau transepidermique augmente en conditions d'atmosphere seche. Ceci touche particulierement la peau du contour de l'oeil, ou la peau est tres fine, et des rides se forment facilement. Un traitement avec le Gel Lamellaire a rapidement resorbe ces rides et hydrate l'epiderme pour une longue duree © Rapid Science Ltd. 1998

Notes: The perpendicular magnetic anisotropy constant in giant magnetoresistive granular Co22Ag78 thin films is found to increase and then decrease with annealing temperature, the maximum being about 5×105 ergs/cc at an annealing temperature of about 600 K. The observation of domain patterns by magnetic force microscopy is consistent with this result. The origin of the perpendicular magnetic anisotropy is not clear, but suggested to be in an anisotropic Co–Co particle distribution and also due to a surface anisotropy of Co particles. © 1999 American Institute of Physics.

Notes: The solid immersion lens (SIL) near-field magneto-optical (MO) recording technique offers a significant increase in areal density through near-field resolution enhancement. Since the near-field recording scheme requires close proximity of the optical recording head and the magnetic medium, the SIL MO recording setup is usually changed to a "first surface" recording. This requires further optimization of the optical flying head design and a MO medium. In this work marks as small as 150 nm using a SIL with a 680 nm laser source and a TbFeCo magneto-optical medium were recorded. The minimum size of a recorded mark is strongly dependent on the slider flying height, the flying attitude, and lens centering. It should be emphasized that recording power as small as 4 mW is sufficient enough to achieve carrier-to-noise ratio of more than 30 dB. © 1999 American Institute of Physics.

Notes: Magnetic and magneto-optical properties of TbFeCo/Pt and TbFeCo/Pd multilayer films prepared by sputter deposition are discussed in conjunction with the multilayer structure. The magnetic behaviors in TbFeCo/Pt and TbFeCo/Pd multilayers are very similar to each other, and the saturation magnetization Ms at 298 K increases with thickness t of Pt and Pd up to tPt, tPd=12 Å. In TbFeCo/Pt multilayers, the contribution of Pt to the polar Kerr spectra is significant at ultraviolet photon energies. The Kerr rotation θK and ellipticity ηK are enhanced with Pt layer thickness and become saturated at tPt=12 Å. On the other hand, little contribution from Pd atoms is found in the TbFeCo/Pd multilayer. © 1999 American Institute of Physics.

Notes: The origin of the large perpendicular magnetic anisotropy constant Ku obtained in Co3Pt alloy thin films is discussed in connection with a superlattice structure. The Ku and the order parameter S are influenced not only by substrate deposition temperature Ts but also deposition rate γ. For Ts=330 °C, Ku and S increase with lowering γ, whereas for Ts=400 °C, the opposite trend is found. A model, in which the origin of Ku results from two mechanisms: Magnetocrystalline anisotropy in Co3Pt disordered phase and interface-induced magnetic anisotropy in Co3Pt ordered phase, can account for the observed dependence of Ku on S. © 1999 American Institute of Physics.

Notes: Micromagnetic studies of the magnetization process in high density 5 Gb/in.2 CoCrPtTa and 0.8 Gb/in.2 CoCrTa media were carried out in conjunction with recording performance measurements. The maximum value of the δM curves measured at room temperature and at 373 K is smaller for CoCrPtTa compared to CoCrTa which indicates lesser intergranular exchange coupling in the quaternary medium. At room temperature, the Barkhausen volume V*, which is the smallest switching unit in magnetization reversal, corresponds approximately to one grain for CoCrPtTa but to three to four grains for CoCrTa. These results are consistent with the lower media noise found for CoCrPtTa especially at high bit densities. A decrease in V* to the size of one grain for CoCrTa is observed for temperatures below 200 K. The reduced intergranular exchange is confirmed by δM measurements at 77 K. Low coupling, however, leads to low values of Mr which leads to a reduction in the reading signal. The value of Mr for CoCrTa at 77 K is 60% greater than that of CoCrPtTa at room temperature despite the reduced exchange coupling indicating that larger values of Mr can still be achieved while confining the switching volume to no more than a grain. © 1997 American Institute of Physics.

Notes: The peak-to-valley ratio of AlSb–InAs resonant tunneling diodes decreases as the diameter of the diode decreases due to the surface current. To clarify the origin of the surface current, we studied AlSb–InAs single-barrier diodes with various diameters and barrier thicknesses at various temperatures. We conclude from experimentally obtained results that bulk current is caused by tunneling through an AlSb barrier influenced by the band structure and surface current is caused by an electron emission from band-gap surface states at the AlSb barrier based on the Poole–Frenkel mechanism with ionization energy of 0.24 eV. © 1999 American Institute of Physics.

Notes: The effect of Pt additives in TbFeCo(Pt)/Pt multilayers on magnetic properties and magneto-optical Kerr effect is investigated. The perpendicular magnetic anisotropy Ku of the multilayer becomes larger (∼2×106 erg/cm3) than that of the TbFeCo(Pt) single layer. Pt layers are found to contribute significantly to the polar Kerr spectra at ultraviolet photon energies beyond 4 eV. The largest enhancement in the Kerr rotation θK is found at about 5 eV. The Kerr rotation θK and ellipticity ηK are enhanced with increasing Pt layer-thickness tPt, and become saturated at tPt=12 Å. This result implies that Pt atoms up to about 6 Å from the interfaces are contributing to the Kerr activity. © 1998 American Institute of Physics.

Notes: The origin of the large perpendicular magnetic anisotropy constant Ku of Co3Pt alloy thin films is discussed. The films deposited onto Al2O3(0001), Al2O3(112¯0), and MgO(111) substrates held at 230–450 °C during deposition exhibit Ku of the order of 107 erg/cm3 at room temperature. While the one dimensional long range order parameter S estimated by x-ray diffraction is very consistent with the development of the perpendicular magnetic anisotropy in the films deposited at 380–450 °C, very little evidence is found to suggest the correlation between S and Ku for the lower deposition temperature range (230–380 °C). To explain this, a short range ordering is suggested to be responsible for the origin of Ku, similar to the cases in Pt72Co28 alloys. The magneto-optical polar Kerr activity of ordered Co3Pt film is found to be enhanced for both θK and ηK in the photon energy range from 2 to 4 eV. © 1998 American Institute of Physics.