Coherent information

About: Coherent information is a research topic. Over the lifetime, 1225 publications have been published within this topic receiving 46672 citations.

Information theory based on nonadditive information content.

Abstract: We generalize Shannon's information theory in a nonadditive way by focusing on the source coding theorem. The nonadditive information content we adopted is consistent with the concept of the form invariance structure of the nonextensive entropy. Some general properties of the nonadditive information entropy are studied, in addition, the relation between the nonadditivity q and the codeword length is pointed out.

Revisiting the Dolinar receiver through multiple-copy state discrimination theory

Abstract: We consider the problem of discriminating between two quantum coherent states by interpreting a single state as being a collection of several successive copies of weaker coherent states. By means of recent results on multiple-copy state discrimination, it is possible to give a reinterpretation of the Dolinar receiver and carry out a quite-straightforward analysis of its behavior. We also propose and investigate a suboptimal detection scheme derived from the Dolinar's architecture, which is shown to slightly outperform some other near-optimal schemes available in the literature.

Classical and Quantum Information Theory

Abstract: The properties of classical and quantum information are very different. Classical information is carried by systems with a definite state, and it can be replicated and measured without being altered. Quantum information is encoded as a property of quantum systems (e.g., photon polarization or particle and has special properties such as superposition and entanglement with no classical counterpart; quantum information cannot be cloned, and it is altered as a result of a measurement. This chapter discusses the physical support of information and overviews several properties of classical information based on Shannon's theory, concentrating on the properties of quantum information, sources and, quantum channels. The Landauer principle relates information with thermodynamic entropy. Once the thermodynamic effect of information erasure is established, the physical nature of information can be quantified. The amount of information that can be stored or transmitted by a physical system is related to the number of states the system. The entropy, an important concept in thermodynamics, Shannon's information theory, as well as quantum information theory, is a function of the logarithm of the number of states of a system; this logarithm is equal to the number of bits required to uniquely identify the state of the system—in other words, to label a state. The label becomes an element of the state and any state transformation will affect the label; to prepare a system in a certain state, the label of the previous state has to be erased. Shannon entropy is used to characterize a source of classical information as well as the properties of a classical communication channel.

A Brief Introduction to Information Theory

Abstract: This chapter contains sections titled: Classical Information Information Content in a Signal Entropy and Shannon's Information Theory Probability Basics Exercises