Novel Quantum Condensates in Excitonic Matter
Abstract
These lectures interleave discussion of a novel physical problem of a new kind of condensate with teaching of the fundamental theoretical tools of quantum condensed matter field theory. Polaritons and excitons are light mass composite bosons that can be made inside solids in a number of different ways. As bosonic particles, they are liable to make a phase coherent ground state  generically called a BoseEinstein condensate (BEC)  and these lectures present some models to describe that problem, as well as general approaches to the theory. The focus is very much to explain how meanfieldlike approximations that are often presented heuristically can be derived in a systematic fashion by path integral methods. Going beyond the mean field theory then produces a systematic approach to calculation of the excitation energies, and the derivation of effective low energy theories that can be generalised to more complex dynamical and spatial situations than is practicable for the full theory, as well as to study statistical properties beyond the semiclassical regime. in particular, for the polariton problem, it allows one to connect the regimes of equilibrium BEC and nonequilibrium laser. The lectures are selfsufficient, but not highly detailed. The methodological aspects are covered inmore »
 Authors:

 Cavendish Laboratory, Madingley Road, Cambridge CB3 OHE (United Kingdom)
 Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom)
 Departamento de Fisica Teorica de la Materia Condensada, Universidad Autonoma de Madrid, Madrid 28049 (Spain)
 Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom)
 Publication Date:
 OSTI Identifier:
 21344503
 Resource Type:
 Journal Article
 Journal Name:
 AIP Conference Proceedings
 Additional Journal Information:
 Journal Volume: 1162; Journal Issue: 1; Conference: 13. training course in the physics of strongly correlated systems, Salerno (Italy), 617 Oct 2008; Other Information: DOI: 10.1063/1.3225478; (c) 2009 American Institute of Physics; Journal ID: ISSN 0094243X
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; BOSEEINSTEIN CONDENSATION; EXCITATION; EXCITONS; GROUND STATES; LASER RADIATION; MEANFIELD THEORY; PATH INTEGRALS; PHONONS; POLARONS; QUANTUM FIELD THEORY; SEMICONDUCTOR MATERIALS; SOLIDS; CALCULATION METHODS; ELECTROMAGNETIC RADIATION; ENERGY LEVELS; ENERGYLEVEL TRANSITIONS; FIELD THEORIES; INTEGRALS; MATERIALS; QUASI PARTICLES; RADIATIONS
Citation Formats
Littlewood, P B, Keeling, J M. J., Simons, B D, Eastham, P R, Marchetti, F M, and Szymanska, M H. Novel Quantum Condensates in Excitonic Matter. United States: N. p., 2009.
Web. doi:10.1063/1.3225478.
Littlewood, P B, Keeling, J M. J., Simons, B D, Eastham, P R, Marchetti, F M, & Szymanska, M H. Novel Quantum Condensates in Excitonic Matter. United States. doi:10.1063/1.3225478.
Littlewood, P B, Keeling, J M. J., Simons, B D, Eastham, P R, Marchetti, F M, and Szymanska, M H. Thu .
"Novel Quantum Condensates in Excitonic Matter". United States. doi:10.1063/1.3225478.
@article{osti_21344503,
title = {Novel Quantum Condensates in Excitonic Matter},
author = {Littlewood, P B and Keeling, J M. J. and Simons, B D and Eastham, P R and Marchetti, F M and Szymanska, M H},
abstractNote = {These lectures interleave discussion of a novel physical problem of a new kind of condensate with teaching of the fundamental theoretical tools of quantum condensed matter field theory. Polaritons and excitons are light mass composite bosons that can be made inside solids in a number of different ways. As bosonic particles, they are liable to make a phase coherent ground state  generically called a BoseEinstein condensate (BEC)  and these lectures present some models to describe that problem, as well as general approaches to the theory. The focus is very much to explain how meanfieldlike approximations that are often presented heuristically can be derived in a systematic fashion by path integral methods. Going beyond the mean field theory then produces a systematic approach to calculation of the excitation energies, and the derivation of effective low energy theories that can be generalised to more complex dynamical and spatial situations than is practicable for the full theory, as well as to study statistical properties beyond the semiclassical regime. in particular, for the polariton problem, it allows one to connect the regimes of equilibrium BEC and nonequilibrium laser. The lectures are selfsufficient, but not highly detailed. The methodological aspects are covered in standard quantum field theory texts and the presentation here is deliberately cursory: the approach will be closest to the book of Altland and Simons. Since these lectures concern a particular type of condensate, reference should also be made to texts on BEC, for example by Pitaevskii and Stringari. A recent theoretically focussed review of polariton systems covers many of the technical issues associated with the polariton problem in greater depth and provides many further references.},
doi = {10.1063/1.3225478},
journal = {AIP Conference Proceedings},
issn = {0094243X},
number = 1,
volume = 1162,
place = {United States},
year = {2009},
month = {8}
}