2009/03/16 by Brendon W. Lovett, Brendon W Lovett, Ahsan Nazir
Engineering · Physics and Astronomy · #Molecular Communication and Nanonetworks #Nanotechnology research and applications #Spectroscopy and Quantum Chemical Studies #quant-ph
paper · pdf · doi:10.1088/0143-0807/30/4/s08
published as European Journal of Physics 30 S89 (2009) · Invited review paper at an introductory level, aimed at an undergraduate audience. To appear in European Journal of Physics, Special feature on Nanotechnology. 14 pages, 4 figures
arxiv created 2009/03/16 · openalex publication_date 2009/07/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Coherence is a familiar concept in physics. It is the driving force behind wavelike phenomena such as the diffraction of light. Moreover, wave–particle duality implies that all quantum objects can exhibit coherence, and this quantum coherence is crucial to understanding the behaviour of a plethora of systems. In this paper, which is written at an undergraduate level, we shall briefly introduce what is meant by coherence in a well-known classical setting, before going on to describe its quantum version. We will show that coherence is important in describing the properties of solid-state nanosystems and especially quantum dots. Simple experiments that reveal the coherent nature of matter—and how this leads to some very powerful applications—will be described. Finally, we shall discuss the fragility of coherence and shall introduce a method for describing decoherence in open quantum systems.