Quantitative quantum erasure

Quantum erasure aims at large fringe visibility in sorted subensembles. Sin ce the achieved visibility depends on the specific sorting scheme, we optim ize the sorting procedure under general circumstances. The possible comprom ises between fringe visibility (wave-typical) and which-alternative knowled ge (particle-typical) are governed by a number of inequalities that are qua ntitative statements about wave-particle duality. Among them is the 'erasur e relation', which stares an absolute upper bound on the visibility that a quantum eraser can yield. (C) 2000 Elsevier Science B.V. All rights reserve d.