caa a22 4500 463215176 CHVBK 20180405153154.0 cr unu---uuuuu 170326e20070601xx s 000 0 eng 10.1007/s00339-007-3974-0 doi (NATIONALLICENCE)springer-10.1007/s00339-007-3974-0 Lengeler B. 2. Physikalisches Institut, RWTH Aachen, Templergraben 55, 52056, Aachen, Germany aut Coherence [Elektronische Daten] [B. Lengeler] The concept of coherence is widely used in different areas of physics like in optics, in quantum optics or in neutron and X-ray scattering, however with subtle differences in meaning for the different communities. In quantum optics it is mainly the source of photons and its characterization in terms of coherence functions which is of concern. In a scattering experiment, on the other hand, the source is supposed to be characterized and it is the internal degrees of freedom of the sample which are studied via their influence on the detected interference pattern. It is one of the purposes of this paper to clarify the different concepts and to show how they are interrelated. The paper is organized as follows. First, we will discuss what interferes in a physical event. This will be treated according to the Feynman formulation of quantum mechanics in terms of probability amplitudes and we will describe nine rules on how to calculate with these amplitudes. Then we will discuss what destroys interference. The main part of the paper treats a number of applications from quantum optics and X-ray and neutron scattering. These include quantum beats, Hanbury Brown and Twiss interferometry, entangled states, Einstein-Podolsky-Rosen paradox and speckle from coherently illuminated samples. Springer-Verlag, 2007 Applied Physics A Springer-Verlag 87/3(2007-06-01), 585-592 0947-8396 87:3<585 2007 87 339 https://doi.org/10.1007/s00339-007-3974-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00339-007-3974-0 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Lengeler B. 2. Physikalisches Institut, RWTH Aachen, Templergraben 55, 52056, Aachen, Germany aut NATIONALLICENCE 773 0- Applied Physics A Springer-Verlag 87/3(2007-06-01), 585-592 0947-8396 87:3<585 2007 87 339 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer