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We present a general phenomenological theory for chemical to mechanical energy transduction by motor enzymes which is based on the classical "tight-coupling" mechanism. The associated minimal stochastic model takes explicitly into account both ATP hydrolysis and thermal noise effects. It provides expressions for the hydrolysis rate and the sliding velocity,(More)
Classical hard spheres crystallize at equilibrium at high enough density. Crystals made up of stackings of 2-dimensional hexagonal close-packed layers (e.g. f cc , hcp , etc.) differ in entropy by only about 10 −3 k B per sphere (all configurations are degenerate in energy). To readily resolve and study these small entropy differences, we have implemented(More)
We use the density matrix renormalization group to perform accurate calculations of the ground state of the nearest-neighbor quantum spin S = 1/2 Heisenberg antiferromagnet on the kagome lattice. We study this model on numerous long cylinders with circumferences up to 12 lattice spacings. Through a combination of very-low-energy and small finite-size(More)
We have studied the ordering dynamics of the striped patterns of a single layer of cylindrical block copolymer microdomains in a thin film. By tracking disclinations during annealing with time-lapse atomic force microscopy, we observe a dominant mechanism of disclination annihilation involving three or four disclinations (quadrupoles). Pairwise disclination(More)
We use ideas from kinetic proofreading, an error-correcting mechanism in biology, to identify new kinetic regimes in non-equilibrium systems. These regimes are defined by the sensitivity of the occupancy of a state of the system to a change in its energy. In biological contexts, higher sensitivity corresponds to stronger discrimination between molecular(More)
We calculate the contribution of superconducting fluctuations to thermal transport in the normal state, at low magnetic fields. We do so in the Gaussian approximation to their critical dynamics which is also the Aslamazov-Larkin approximation in the microscopics. Our results for the thermal conductivity tensor and the transverse thermoelectric response are(More)
Electronic states in disordered conductors on the verge of localization are predicted to exhibit critical spatial characteristics indicative of the proximity to a metal-insulator phase transition. We used scanning tunneling microscopy to visualize electronic states in Ga(1-x)Mn(x)As samples close to this transition. Our measurements show that doping-induced(More)
We present an adaptive algorithm which optimizes the statistical-mechanical ensemble in a generalized broad-histogram Monte Carlo simulation to maximize the system's rate of round trips in total energy. The scaling of the mean round-trip time from the ground state to the maximum entropy state for this local-update method is found to be O ( [N ln N](2) ) for(More)
We solve for the time-dependent finite-size scaling functions of the one-dimensional transverse-field Ising chain during a linear-in-time ramp of the field through the quantum critical point. We then simulate Mott-insulating bosons in a tilted potential, an experimentally studied system in the same equilibrium universality class, and demonstrate that(More)
Ultracold atoms in optical lattices have great potential to contribute to a better understanding of some of the most important issues in many-body physics, such as high-temperature superconductivity. The Hubbard model--a simplified representation of fermions moving on a periodic lattice--is thought to describe the essential details of copper oxide(More)