Diamond-like carbon (DLC) is a metastable form of amorphous carbon with significant sp3 bonding. DLC is a semiconductor with a high mechanical hardness, chemical inertness, and optical transparency. This review will describe the deposition methods, deposition mechanisms, characterisation methods, electronic structure, gap states, defects, doping, luminescence, field emission, mechanical properties and some applications of DLCs. The films have widespread applications as protective coatings in areas, such as magnetic storage disks, optical windows and micro-electromechanical devices (MEMs).

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Diamond-like amorphous carbon

The unprecedented ability of nanometallic (that is, plasmonic) structures to concentrate light into deep-subwavelength volumes has propelled their use in a vast array of nanophotonics technologies and research endeavours. Plasmonic light concentrators can elegantly interface diffraction-limited dielectric optical components with nanophotonic structures. Passive and active plasmonic devices provide new pathways to generate, guide, modulate and detect light with structures that are similar in size to state-of-the-art electronic devices. With the ability to produce highly confined optical fields, the conventional rules for light-matter interactions need to be re-examined, and researchers are venturing into new regimes of optical physics. In this review we will discuss the basic concepts behind plasmonics-enabled light concentration and manipulation, make an attempt to capture the wide range of activities and excitement in this area, and speculate on possible future directions.

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Plasmonics for extreme light concentration and manipulation.

Singular Integral Equations. By N.I. Muskhelishvili. Translated fromthe 2nd Russian edition by J.R.M. Radok. Pp. 447. F1. 28.50. 1953. (Noordhoff, Groningen)

Our aim is to propose a theory which goes beyond the classical formulation of thermodynamics. This is achieved by enlarging the space of basic independent variables, through the introduction of non-equilibrium variables, such as the dissipative fluxes appearing in the balance equations. The next step is to find evolution equations for the dissipative fluxes. Whereas the evolution equations for the classical variables are given by the usual balance laws, no general criteria exist concerning the evolution equations of the dissipative fluxes, with the exception of the restrictions imposed on them by the second law of thermodynamics.

https://iopscience.iop.org/article/10.1088/0034-4885/51/8/002/pdf

Extended irreversible thermodynamics

Surface-tension-driven flows and, in particular, their tendency to decay spontaneously into drops have long fascinated naturalists, the earliest systematic experiments dating back to the beginning of the 19th century. Linear stability theory governs the onset of breakup and was developed by Rayleigh, Plateau, and Maxwell. However, only recently has attention turned to the nonlinear behavior in the vicinity of the singular point where a drop separates. The increased attention is due to a number of recent and increasingly refined experiments, as well as to a host of technological applications, ranging from printing to mixing and fiber spinning. The description of drop separation becomes possible because jet motion turns out to be effectively governed by one-dimensional equations, which still contain most of the richness of the original dynamics. In addition, an attraction for physicists lies in the fact that the separation singularity is governed by universal scaling laws, which constitute an asymptotic solution of the Navier-Stokes equation before and after breakup. The Navier-Stokes equation is thus continued uniquely through the singularity. At high viscosities, a series of noise-driven instabilities has been observed, which are a nested superposition of singularities of the same universal form. At low viscosities, there is rich scaling behavior in addition to aesthetically pleasing breakup patterns driven by capillary waves. The author reviews the theoretical development of this field alongside recent experimental work, and outlines unsolved problems.

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Nonlinear dynamics and breakup of free-surface flows

The Elastostatic Axisymmetric Problem of a Cracked Sphere

Effect of Functional End-Groups on the Lubricant Recovery After Heat-Assisted Magnetic Recording (HAMR) Writing

Intermolecular and surface forces contribute significantly to the total forces acting on air bearing sliders for flying heights below 5nm. Their contributions to the total forces increase sharply with the reduction in flying height, and hence their existence can no longer be ignored in air bearing simulation for hard disk drives. Various experimentally observed dynamic instabilities can be explained by the inclusion of these forces in the model for low flying sliders. In this paper parametric studies are presented using a 3-DOF model to better understand the effect of the Hamaker constants, suspension pre load and pitch angle on the dynamic stability/instability of the sliders. A stiffness matrix is used to characterize the stability in the vertical, pitch and roll directions. The fly height diagrams are used to examine the multiple equilibriums that exist for low flying heights. It has been found that the system instability increases as the magnitude of the van der Waals force increases. It has also been found that higher suspension pre load and higher pitch angles tend to stabilize the system.Copyright © 2004 by ASME

Effect of Intermolecular Forces on the Static and Dynamic Performance of Air Bearing Sliders: Part II — Dependence of the Stability on Hamaker Constant, Suspension Preload and Pitch Angle

Tunability of Recording Head Protrusion by Use of Embedded Dual Heaters

In order to estimate the contact stress and deformation at the instant of head-disk impact during dynamic loading, Hertz's impact theory is implemented in a dynamic loading numerical simulator. By using a finite difference model for the air bearing, a finite element model for the slider-flexure-suspension system, and Hertz's contact model of head-disk impact, we obtain estimates of contact stress, area and time through simulation of the dynamic loading process. With our choice of the material properties and geometric configurations, the duration of sliding contact is about 7 μs, the maximum width of contact is about 10 μm, and the maximum contact stress is about 620 MPa. This is below the yield stresses of the chosen media.

David B. Bogy

Papers

The Elastostatic Axisymmetric Problem of a Cracked Sphere

Effect of Functional End-Groups on the Lubricant Recovery After Heat-Assisted Magnetic Recording (HAMR) Writing

Effect of Intermolecular Forces on the Static and Dynamic Performance of Air Bearing Sliders: Part II — Dependence of the Stability on Hamaker Constant, Suspension Preload and Pitch Angle

Tunability of Recording Head Protrusion by Use of Embedded Dual Heaters

Numerical Simulation of Head-Disk Impacts During Dynamic Loading Processes