The study of quantum fluids in three dimensions has been an important area for many years as it embraces Bose-Einstein condensation, superfluidity and macroscopic quantisation. These are fundamental aspects of physics which can be studied in liquid 4He. In contrast, quantum fluids in two dimension is more recent and less developed. Nevertheless it has shown many interesting phenomena including a rich variety of phases and the Kosterlitz-Thouless transition. Intermediate between these dimensions are the restricted geometries of micro porous materials into which He may be introduced. The main quantum materials considered are 4He, 3He, D2, H2, H and electrons on the surface of 4He. The superfluid phases of 3He were excluded, e~cept for superfluid film flow, as 3He involves a separate set of problems. These proceedings arise from a lively Advanced Research Workshop on Excitations in Two-Dimensional and Three-Dimensional Quantum Fluids held in Exeter 10-15 August 1990. Fifty scientists took part and each provided a written contribution. Perhaps it is a testimony to the discussions that several papers were revised by the authors after the meeting. The order of the chapters is the same as the presentations at the workshop. This arrangement starts with 4He in three dimensions which establishes a base from which the two dimensional properties can be viewed. At the end of each section there is a report on the discussion session. These are interesting and useful chapters as they clarify points made in the papers and define the boundary of current understanding.
Reihe
Physics (Continued Within NATO Science Series II: Mathematics, Physics and Chemistry)
257
Auflage
Sprache
Verlagsort
Verlagsgruppe
Springer Science+Business Media
Zielgruppe
Für höhere Schule und Studium
Für Beruf und Forschung
Illustrationen
Maße
Gewicht
ISBN-13
978-0-306-43913-1 (9780306439131)
DOI
10.1007/978-1-4684-5937-1
Schweitzer Klassifikation
Excitations in Liquid 4He.- Excitations in Superfluid 4He and the Dielectric Formalism.- Recent High-Resolution Neutron Scattering Studies of Liquid 4He.- Momentum Distributions in Liquid Helium.- S(Q,?) for Liquid 4He: What More do we Need to Know?.- Raman Scattering from Superfluid Helium.- Interpretation of Inelastic Light Scattering Measurements in 4He.- Discussion on Excitations in Bulk4He.- Excitations in Liquid Helium at Negative Pressures.- Neutron Spin Echo Observation of Spontaneous Phonon Decay in Superfluid 4He.- Dynamics of Rotons.- Spectroscopic Study of Scattering of UCN by Liquid 4He.- Roton-Roton Scattering.- Theory of Roton-Roton Scattering.- Theory of the Phonon-Roton Spectrum of Liquid. 4He.- Towards a Unified Description of Bulk Excitations and the Two Fluid Theory of Superfluids in Terms of a Single Classical Equation of Motion.- Discussion on Bulk 4He Dynamics.- Bulk Properties of 3He-4He Mixtures.- Transport Properties of Very Dilute Superfluid Mixtures of 3He in 4He.- Anomalous Thermal Conductivity in Very Dilute 3He-4He Solutions.- Thermal Counterflow in Superfluid 3He-4He Mixtures.- Elementary Excitations in Fermi Liquids: Neutron Scattering by 3He and 3He-4He Mixtures.- The Effect of Film Thickness and the Substrate on Superfluid 3He Film Flow.- Discussion on Bulk 3He and 3He/4He Mixtures.- Collective Excitations and Fermi-Liquid Effects in 4He and 3He-4He Films.- NMR Measurements of 3He in 3He-4He Mixture Films.- Fermion Oceans.- Studies of Dissipative Superflow Through Porous Vycor Glass.- Low Temperature Heat Capacity of 4He Films in Vycor.- Vortices and the Superfluid 4He Phase Transition in Two and Three Dimensions.- Scaling of Confined 4He at the Superfluid Transition.- Dynamics of Helium Clusters.- Phase-Slippage Studies of the Critical Velocity in Helium-4.- Discussion on Restricted Geometry.- The Intertia of the 4He Crystal Surface and the Calculation of the Phonon Transmission.- Thermal Excitations and Helium 3 Crystallization.- Anisotropy of Surface Stiffness, Growth Kinetics and Roughening Transition in 4He.- Liquid-Solid 4He Interface: Equilbrium Shape and Excitations.- Charge Motion in Solid Helium.- 4He Films on Graphite Studied by Neutron Scattering.- Interface Between Two Thin 3He-4He Liquid Mixtures Films.- Discussion on Interfaces.- Adsorbed Quantum Gases.- Nuclear Magnetism of 3He Films Adsorbed on the Surface of Graphite.- Low-Field NMR Studies of the Boundary Layers of 3He on Grafoil.- Search for a Fluid Phase in Films of Molecular Hydrogen Isotopes Adsorbed on MgO.- Lattice Dynamics of Quantum Gases Adsorbed on Graphite Investigated by Inelastic Neutron Scattering.- Thermodynamic and Neutron-Diffraction Studies of H2 and D2 Multilayers Physisorbed on Graphite.- Scattering of Atomic Hydrogen from the Surface of Liquid Helium Films.- Discussion on Adsorbates.- Electrons at the Surface of Quantum Systems.- Electrons on Helium Films.- Tunneling and Evaporation from the Electron Liquid Trapped at a Helium Surface.- Electrons on Helium in a Quantizing Magnetic Field.- Vortex Creation in Superfluid Helium-4.- Ions Trapped Below the Surface of Superfluid Helium.- Discussion on Ions/Electrons.- Final Discussion Session.
