Aspects of Quantum Coherence in Nanosystems

TL;DR

This paper introduces quantum coherence, its significance in nanosystems like quantum dots, and discusses experimental methods and the fragility of coherence, including decoherence in open quantum systems.

Contribution

It provides an accessible overview of quantum coherence in nanosystems, highlighting its importance, experimental observations, and the modeling of decoherence processes.

Findings

Quantum coherence is fundamental in nanosystems.

Experiments demonstrate coherence in quantum dots.

Decoherence can be modeled in open quantum systems.

Abstract

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 article, 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.