Anomalous temperature dependence ofD andT 2 for dilute solutions of3He in solid4He

Allen, Alastair Robert; Richards, M. G.; Schratter, J.

doi:10.1007/bf00683732

Cited by 80 publications

(41 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The fit may be improved by further variation of the parameters, but this does not seem reasonable, considering the approximations made. It is seen that the activation energy Φ is in good agreement with what has been observed experimentally [28] and increases with decreasing molar volume as it should. The band width also manifests a strong molar dependence changing almost two times from V m = 21 cm 3 to V m = 20.60 cm 3 .…”

Section: Comparison With Experiment Determination Of the Impuriton Csupporting

confidence: 88%

“…The same dependence on ∆ follows also from the theories of Landesman [26] and Yamashita [27] for interacting quasiparticles. This coincidence is evidently the explanation of the fact that the dependence of the diffusion coefficient on the molar volume ("the Grüneisen parameter") does not vary with decreasing concentration [28] (see below). The condition (22) can be satisfied at lower temperatures as well if the following inequalities are valid:…”

Section: Defecton-defecton Scatteringmentioning

confidence: 73%

“…Let us now show the order of calculation of defecton characteristics on the basis of the data in Table 1. Estimation will be made for V m = 21 cm 3 , x = 0.05%, B = 2.8 × 10 −11 [28]. …”

Section: Comparison With Experiment Determination Of the Impuriton Cmentioning

confidence: 99%

“…The experimental points are from Ref. [28]. The fit may be improved by further variation of the parameters, but this does not seem reasonable, considering the approximations made.…”

Section: Comparison With Experiment Determination Of the Impuriton Cmentioning

confidence: 99%

See 3 more Smart Citations

Quantum diffusion

Pushkarov

2004

Open Physics

View full text Add to dashboard Cite

Basic ideas and results which characterize quantum diffusion of defects in quantum crystals like solid helium as a new phenomenon are presented. Quantum effects in such media lead to a delocalization of point defects (vacancies, impurities etc.) and they turn into quasiparticles of a new type -defectons, which are characterized not by their position in the crystal lattice but by their quasimomentum and dispersion law. Defectondefecton and defecton-phonon scattering are considered and an interpolation formula for the diffusion coefficient valid in all interesting temperature and concentration regions is presented. A comparison with the experimental data is made. Some alternative points of view are discussed in detail and the inconsistency of the Kisvarsanyi-Sullivan theory is shown.

show abstract

Section: Comparison With Experiment Determination Of the Impuriton Csupporting

confidence: 88%

Section: Defecton-defecton Scatteringmentioning

confidence: 73%

“…Let us now show the order of calculation of defecton characteristics on the basis of the data in Table 1. Estimation will be made for V m = 21 cm 3 , x = 0.05%, B = 2.8 × 10 −11 [28]. …”

Section: Comparison With Experiment Determination Of the Impuriton Cmentioning

confidence: 99%

“…The experimental points are from Ref. [28]. The fit may be improved by further variation of the parameters, but this does not seem reasonable, considering the approximations made.…”

Section: Comparison With Experiment Determination Of the Impuriton Cmentioning

confidence: 99%

See 2 more Smart Citations

Quantum diffusion

Pushkarov

2004

Open Physics

View full text Add to dashboard Cite

show abstract

“…Local atomic motion along the other directions is assumed to be severly restricted due to the higher excitation energies (Fig.1). Experimental evidence for the existence of such a "local mode" comes from NMR measurements which find an activation energy of 7±1K 4,5 , and we propose to identify this local-mode with the highly directional motion of the atoms in the normal directions.…”

Section: Introductionmentioning

confidence: 93%

bcc4Heas a coherent quantum solid

Gov

2000

Phys. Rev. B

View full text Add to dashboard Cite

In this work we investigate implications of the quantum nature of bcc 4 He. We show that it is a unique solid phase with both a lattice structure and an Off-Diagonal Long Range Order of coherently oscillating local electric dipole moments. These dipoles arise from the local motion of the atoms in the crystal potential well, and oscillate in synchrony to reduce the dipolar interaction energy. The dipolar ground-state is therefore found to be a coherent state with a well defined global phase and a three-component complex order parameter. The condensation energy of the dipoles in the bcc phase stabilizes it over the hcp phase at finite temperatures. We further show that there can be fermionic excitations of this ground-state and predict that they form an optical-like branch in the (110) direction. A comparison with 'super-solid' models is also discussed.

show abstract

On the defecton statistics in quantum crystals

Pushkarov

1986

Physica Status Solidi (b)

View full text Add to dashboard Cite

The defecton statistics in quantum crystals is treated, and a new method for determining commutation relations is proposed. Defectons related to defects of a different kind (vacancies, impurities, interstitials) are considered in crystals both of the Bose-type (4He) and Fermi-type (3He). The kinematic interaction is discussed.Es wird die Statistik von Defektonen in Quantenkristallen behandelt und eine neue Methode zur Bestimmung der Vertauschungsrelationen vorgeschlagen. Defektonen, hervorgerufen durch verschiedenartige Defekte (Leerstellen, Verunreinigungen, Zwischengitteratome), werden sowohl fur Kristalle vom Bose-Typ (4He) als auch fur Kristalle vom Fermi-Typ ($He) betrachtet. Die kinematische Wechselwirkung wird diskutiert.

show abstract

Anomalous temperature dependence ofD andT 2 for dilute solutions of3He in solid4He

Cited by 80 publications

References 37 publications

Quantum diffusion

Quantum diffusion

bcc4Heas a coherent quantum solid

On the defecton statistics in quantum crystals

Contact Info

Product

Resources

About