Abstract
A quantum crystal is one in which the zero point motion of an atom about its equilibrium position is a large fraction of the near neighbor distance. Both short range correlations and long range correlations (phonons) are of importance and must be treated with care in the description of quantum crystals. Recently, considerable progress has been made along these lines. This chapter discusses this progress. It discusses the gross properties of the rare gas solids (mostly solid helium). Particular attention is given to the interplay of “mass” and “interaction” which leads to an expanded lattice and the large zero point motion. It examines the Hartree approximation to the ground state energy of solid helium in order to illustrate the need for including short range correlations in the description of the system. This chapter describes a number of treatments of the short range correlation problem. The first successful theory of the ground state energy in quantum crystals is due to Nosanow. The “theory of correlated crystals” due to Brueckner and FrohbergZ and the “quasi-crystal approximation” of Maasey and Woo are also discussed in this chapter.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
