Information-Theoretic Aspects of Quantum Copying

Eduard Prugovečki

Roman S. Ingarden

Samuel L. Braunstein

Given a single copy of an unknown quantum state, it is impossible in principle to identify it. The mostly inaccessible information carried by the state is termed quantum information. In contrast to classical information, it cannot be copied or cloned. This concept provides a theoretical underpinning for all aspects of quantum communication and quantum computation. Here we use it to consider quantum teleportation.

Lev B. Levitin

Сыч Денис Васильевич, B. A. Grishanin, Victor N. Zadkov

Information aspects of copying quantum states via stimulated emission of an optical quantum amplifier are considered. It is shown that the measurable information very rapidly decreases after amplification of a single photon up to a level of several photons. Spontaneous emission, which leads to such behavior, is also discussed.

Nicolas C. Menicucci