Structural transformation and localization during simulated nanoindentation of a non-crystalline metal film

A simulation study demonstrates that localization can arise as the result of the breakdown of stable quasi-crystal-like atomic configurations. Samples produced at elevated quench rates and via more energetic processes contain a lower fraction of such configurations and exhibit significantly less pronounced localization and shorter spacing between bands. In the samples produced by the lowest quench rates localization is accompanied by the amorphization of material with initially quasi-crystal-like medium range order. This result is of particular significance in light of recent experimental evidence of local quasi-crystal order in the most stable of the bulk metallic glasses.Comment: 13 pages, 3 figure

On the KP Hierarchy, W^∞\hat{W}_{\infty} Algebra, and Conformal SL(2,R)/U(1) Model: II. The Quantum Case

This paper is devoted to constructing a quantum version of the famous KP hierarchy, by deforming its second Hamiltonian structure, namely the nonlinear $\hat{W}_{\infty}$ algebra. This is achieved by quantizing the conformal noncompact $SL(2,R)_{k}/U(1)$ coset model, in which $\hat{W}_{\infty}$ appears as a hidden current algebra. For the quantum $\hat{W}_{\infty}$ algebra at level $k=1$, we have succeeded in constructing an infinite set of commuting quantum charges in explicit and closed form. Using them a completely integrable quantum KP hierarchy is constructed in the Hamiltonian form. A two boson realization of the quantum $\hat{W}_{\infty}$ currents has played a crucial role in this exploration.Comment: 33