几何相位的光外差探测

众所周知,几何因子在物理学中起着重要作用。例如Minkowski借助于时空几何对狭义相对论的几何重建对爱因斯坦建立广义相对论非常有用。但量子理论一直缺乏几何途径,直到1984年才由Berry引入。Berry发现,一个绝热展演的量子系统在循环演变中存在一个与时间无关的,仅取决于相互作用“路径”的几何相位因子。他的论证在国际物理学界引起巨大反响,从而解释了许多不同学科分支中悬而未决的问题。该因子现又被重建和一般化而适用于非绝热循环演变(例如能级跃迁)。

评用炼厂干气取代轻油制氢制氨

介绍国内外用炼厂干气制氢、制氨概况，对３种炼厂干气加氢流程进行比较，讨论用炼厂干气取代石脑油作为合成氨原料时，对后面工序的影响。

An Alternative Adiabatic Quantum Algorithm for the Hamiltonian Cycle Problem

We put forward an alternative quantum algorithm for finding ttamiltonian cycles in any N-vertex graph based on adiabatic quantum computing. With a yon Neumann measurement on the final state, one may determine whether there is a HamiRonian cycle in the graph and pick out a cycle if there is any. Although the proposed algorithm provides a quadratic speedup, it gives an alternative algorithm based on adiabatic quantum computation, which is of interest because of its inherent robustness.