On the Informational Aspects of Interfering Quantum States

TL;DR

This paper investigates the informational aspects of quantum interference, linking diffraction patterns to Schmidt modes, and explores entanglement limits, tunneling, and molecular modifications through new informational measures.

Contribution

It introduces informational measures to analyze quantum interference quality, relates interference visibility to Schmidt number, and examines entanglement limits in quantum systems.

Findings

Diffraction pattern corresponds to a mixture of Schmidt modes.

Interference visibility is related to the Schmidt number.

Limits on entanglement degree are derived from measurement constraints.

Abstract

In present work we study informational measures for the problem of interference of quantum particles. We demonstrate that diffraction picture in the far field, which is given by probability density of particle momentum distribution, represents a mixture of probability densities of corresponding Schmidt modes, while the number of modes is equal to the number of slits at the screen. Also, for the first time we introduce informational measures to study the quality of interference picture and analyze the relation between visibility of interference picture and Schmidt number. Furthermore, we consider interference aspects of the problem of a quantum particle tunneling between two potential wells. This framework is applied to describing various isotopic modifications of ammonia molecule. Finally, we calculate limits on the maximum possible degree of entanglement between quantum system and its environment, which is imposed by measurements