Double perpendicular recording

Fig. 8. The main-pole driven head in combination with a Co—Cr/Ni—Fe double-layer medium for perpendicular recording.

Double-Layered Zl0 FePtrC/FeCoNi Perpendicular Recording Media... 

For the media preparation, 25-nm-thick CoZrNb soft magnetic film was sputtered onto Ni-P SUL and then a thick CoPtCr-SiC>2 granular recording layer. For comparison, a media with 200-nm-thick sputtered CoZrNb SUL was used. The results showed that an electroless-deposited ferromagnetic Ni-P layer (low phosphorus content), which is suitable for mass production as a SUL for a double-layered perpendicular recording media, exhibits almost the same magnetic properties and recording performances as a 200-nm-thick sputtered SUL. In addition, the spike noise which is commonly observed from SUL was not found for the media with Ni-P SUL. 

Tanahashi K et al (2002) Low-noise EeTaC underlayer for double-layered perpendicular recording media. J Magn Magn Mater 242-245 325-327... 

Sugiyama A (2005) Electroless deposition of soft magnetic underlayer for a double-layered perpendicular recording media. lEICE Tech Rep MR2004-48 15-20... 

Muraoka H et al (1999) Low inductance and high efficiency single-pole writing head for perpendicular double layer recording media. IEEE Trans Magn 35 643-648... 

Figure 1.17 An experimental set-up for electron spectrometry with synchrotron radiation which is well suited to angle-resolved measurements. A double-sector analyser and a monitor analyser are placed in a plane perpendicular to the direction of the photon beam and view the source volume Q. The double-sector analyser can be rotated around the direction of the photon beam thus changing the angle between the setting of the analyser and the electric field vector of linearly polarized incident photons. In this way an angle-dependent intensity as described by equ. (1.55a) can be recorded. The monitor analyser is at a fixed position in space and is used to provide a reference signal against which the signals from the rotatable analyser can be normalized. For all three analysers the trajectories of accepted electrons are indicated by the black areas which go from the source volume Q to the respective channeltron detectors. Reprinted from Nucl. Instr. Meth., A260, Derenbach et al, 258 (1987) with kind permission of Elsevier Science—NL, Sara Burgerhartstraat 25, 1055 KV Amsterdam, The Netherlands.

In this study, dynamic experiments were performed using a differential method of dichroism. The sample was strained in the common beam of a Perkin-Elmer model 180 double-beam spectrophotometer, with the transmitted radiation split into two beams polarized parallel to and perpendicular to the direction of stretch. The recorded output was the difference between the two absorptions. The orientation function was calculated using Equation 3, where A0 is the unpolarized absorption of... 

Fig. 4.3-9 the A -.splitting in the other band is not resolved). The second parallel band (i/[ at 3336.2 cm ) is split much less, due to inversion doubling with AF = 1.8 cm. The P 4 fundamental at 1627 cm is a perpendicular band with the Q branch lines compressed in a smaller spectral interval compared to that of the CHyTspectrum. Another example of a spectrum which resembles those recorded with tower resolution, is the gas phase spectrum of benzene shown in Fig. 4.3-10. The fingerprint region below 2000 cm exhibits the mo.st intense fundamental (v ), which is a parallel band, at 671 cm , The two perpendicular bands at 1485 cm (vis) and 1037 cm (ph) demonstrate similar features.

SRGs recorded with circularly polarized beams showed an even more interesting erasure behavior. The SRG can be erased by beams polarized parallel to the grooves and circularly polarized, as in the previous cases, but when erasing was tried with a beam polarized perpendicularly to the grating grooves an increase in diffraction efficiency and amplification of the surface modulation occurred (44% increase in the amplitude of the SRG, consistent with doubling of the diffraction efficiency). 

The SO2 and NO2 were analyzed independently by two DuPont 400 spectrophotometers. These were double-beam instruments containing analyzer cells maintained at 212 °F. The flue gas passed through the cells continuously. The two analyzers were totally separate except that they shared the same light source the two gas cells were perpendicular to each other. The signals from the NOo and SO2 analyzers were recorded continuously by strip-chart recorders. 

In a double-layered perpendicular magnetic medium, an intermediate layer between a recording layer and an SUL plays an important role as a seed to control the crystal growth of the recording layer and to reduce the magnetic domain size of the recording layer. Moreover, the intermediate layer should be as thin as possible to minimize the... 

Asahi T (2004) Novel soft magnetic underlayer for double-layered perpendicular magnetic recording media Electroless-deposited films of CoNiFe-based alloy. IEEE Trans Magn 40 2356-2358... 

Osaka T (2005) Electroless-deposited soft magnetic underlayer on silicon disk substrate for double-layered perpendicular magnetic recording media. J Magn Magn Mater 287 292-297... 

In the infra-red region, dichroic measurements are conveniently made on double beam instruments, the sample and polariser each being placed in the usual sample beam, and the spectra recorded with the polariser orientation successively parallel and perpendicular to the sample reference axis. If wire grid polarisers are employed, errors due to polariser... 

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