91影视破解版

We design spin filters for particles with potentially arbitrary spin S (=1/2, 1, 3/2, ...) using a one-dimensional periodic chain of magnetic atoms as a quantum device. Describing the system within a tight-binding formalism we present an analytical method to unravel the analogy between a one-dimensional magnetic chain and a multi-strand ladder network. Our scheme is applicable to ultracold quantum gases, and might inspire future experiments in this direction.

Graphene’s flat, homogeneous surface can encourage the growth of large organic semiconducting crystals without relying on epitaxy: a promising development for its application as an electrode material.

The solar wind flows away from the Sun, depositing energy into the magnetosphere as it reaches Earth. Here we explore various ways of quantifying this energy and its variation over the last 20 years.

Ring polymers interpenetrate and “pin” one-another’s motion. To what extent do concentrated solutions, or melts, of ring polymers thread through one another at equilibrium? An analogous system is a well-shaken bucket full of very long rubber bands. If one attempts to withdraw a single rubber band it is very likely that a large tangle of interpenetrating rubber bands will instead emerge. This is to be contrasted with an attempt to withdraw a single strand from a bowl of freshly cooked spagetti, analogous to a system of linear polymers.