You Lung Chen

Abstract: Adhesion and friction experiments were carried out with a variety of surfactant monolayer-coated surfaces using the surface forces apparatus technique. The equilibrium and time-dependent adhesion and the interfacial or'boundary friction of these surfaces were measured as a function of monolayer density and phase state, load, temperature, contact time, sliding speed, and relative humidity. The aim was to investigate the correlations between the friction and adhesion of these fairly ideal, molecularly smooth, and chemically homogeneous surfaces. The results show that friction and adhesion are not generally related if one only compares the magnitude of the friction force (or coefficient of friction) with the adhesion force (or adhesion energy). However, since friction is an energy-dissipating process, one might expect to find a relation between friction and adhesion hysteresis. This was confirmed by comparing the adhesion energy hysteresis during loading-unloading cycles with the friction forces measured under similar conditions. The authors find that -- in spite of its great complexity and dependence on many parameters -- the boundary friction force varies with temperature, sliding velocity, load, and relative humidity in highly systematic ways, which can be represented by a dynamic friction phase diagram. 53 refs., 17 figs., 1 tab.

TL;DR: A quantum central processing unit that exchanges data with a quantum random-access memory integrated on a chip, with instructions stored on a classical computer is demonstrated.

TL;DR: In this paper, the authors found that stray infrared light from the 4 K stage in a cryostat can cause significant loss in superconducting resonators and qubits, consistent with a stray light-induced quasiparticle density of 170-230 \mu m^{-3}.

TL;DR: In this paper, the process of self-assembly of monolayers and bilayers from solution onto molecularly smooth mica surfaces was monitored as a function of time, and it was found that the adsorption or selfassembly of a monolayer or bilayer from solution always occurs in two distinct stages: a fast initial nonequilibrium stage, followed by a much slower phase involving slow molecular and ionic rearrangements toward the final equilibrium state.

TL;DR: In this article, a systematic study of the properties of room temperature deposited TiN films by varying the deposition conditions in an ultra-high-vacuum reactive magnetron sputtering chamber is presented.