Now showing items 21-40 of 57

  • Effect of finite mean free path on spin-flip scattering rates near the critical point of magnetically ordered systems 

    Geldart, D. J. W., and K. De'Bell. 1985. "Effect of finite mean free path on spin-flip scattering rates near the critical point of magnetically ordered systems." Physical Review B (Condensed Matter) 32(5): 3285-8. Copyright © 1985 American Physical Society.
    The finite electron mean free path of conduction electrons is found to play an important role in determining spin-flip scattering rates, 1/sf, near a magnetic critical point. Small-momentum-transfer processes are suppressed ...
  • Surface-induced quantum density oscillations in the presence of an external magnetic field 

    Geldart, D. J. W., G. Gumbs, and M. L. Glasser. 1985. "Surface-induced quantum density oscillations in the presence of an external magnetic field." Physical Review B (Condensed Matter) 31(6): 3315-22. Copyright © 1985 American Physical Society.
    The electron number density and spin density near the surface of a model metal, semimetal, or semiconductor are calculated in the presence of a uniform magnetic field. The magnetic field is applied in a direction perpendicular ...
  • Coefficients to O(3) for the mixed fixed point of the nm-component field model 

    De'Bell, K., and D. J. W. Geldart. 1985. "Coefficients to O(3) for the mixed fixed point of the nm-component field model." Physical Review B (Condensed Matter) 32(7): 4763-5. Copyright © 1985 American Physical Society.
    The nm-component field model has a number of application in the description of critical phenomena. The coefficients in the expansion for the stability matrix eigenvalues and correlation function exponent n for the mixed ...
  • Fourth-order gradient contributions in extended Thomas-Fermi theory for noninteracting fermions at finite temperature 

    Geldart, D. J. W., and E. Sommer. 1985. "Fourth-order gradient contributions in extended Thomas-Fermi theory for noninteracting fermions at finite temperature." Physical Review B (Condensed Matter) 32(12): 7694-702. Copyright © 1985 American Physical Society.
    Nonlocal corrections to the free energy of a system of noninteracting fermions are considered within the framework of extended Thomas-Fermi theory. The density and temperature dependence of gradient corrections is given ...
  • Convergence properties as a function of spatial dimensionality of gradient expansions for the ground-state energy of an inhomogeneous electron gas 

    Geldart, D. J. W., and G. Gumbs. 1986. "Convergence properties as a function of spatial dimensionality of gradient expansions for the ground-state energy of an inhomogeneous electron gas." Physical Review B (Condensed Matter) 33(4): 2820-3. Copyright © 1986 American Physical Society.
    The extended Thomas-Fermi approximation for the ground-state energy of a many-fermion system is generalized to arbitrary spatial dimension. The authors' objective is a better understanding of convergence properties of such ...
  • Exchange and correlation energy in a nonuniform fermion fluid 

    Rasolt, M., and D. J. W. Geldart. 1986. "Exchange and correlation energy in a nonuniform fermion fluid." Physical Review B (Condensed Matter) 34(2): 1325-8. Copyright © 1986 American Physical Society.
    Recent results for the surface energy of jelliumlike surfaces are investigated within the functional-density formalism. These results along with first-principles considerations support the contention that the first gradient ...
  • Nonlocal exchange energy of many-fermion systems of arbitrary dimensionality and interparticle interaction 

    Gumbs, G., and D. J. W. Geldart. 1986. "Nonlocal exchange energy of many-fermion systems of arbitrary dimensionality and interparticle interaction." Physical Review B (Condensed Matter) 34(10): 6847-52. Copyright © 1986 American Physical Society.
    The exchange contributions to the ground-state energy of an inhomogeneous many-fermion system of arbitrary dimensionality are calculated. Explicit results are given for both the local-density approximation and the lowest-order ...
  • Dipole-dipole interactions and the critical resistivity of gadolinium 

    Geldart, D. J. W., K. De'Bell, J. Cook, and M. J. Laubitz. 1987. "Dipole-dipole interactions and the critical resistivity of gadolinium." Physical Review B (Condensed Matter) 35(16): 8876-9. Copyright © 1987 American Physical Society.
    Results are presented for the electrical resistivity of a c-axis single crystal of high-purity gadolinium metal in the immediate vicinity of the Curie temperature. Numerical analysis reveals that the data are not well ...
  • Adsorbate densities and surface potentials of physisorbed systems: A density-functional approach 

    Payne, S. H., H. J. Kreuzer, and D. J. W. Geldart. 1987. "Adsorbate densities and surface potentials of physisorbed systems: A density-functional approach." Physical Review B (Condensed Matter) 35(18): 9489-93. Copyright © 1987 American Physical Society.
    A density-functional approach for the calculation of the density of particles adsorbed on the surface of a solid is explored including the adparticle two-body interaction. The coverages and effective surface potentials so ...
  • Lattice sums for dipolar systems 

    Fujiki, N. M., K. De'Bell, and D. J. W. Geldart. 1987. "Lattice sums for dipolar systems." Physical Review B (Condensed Matter) 36(16): 8512-16. Copyright © 1987 American Physical Society.
    A general method for the evaluation of lattice sums determining the effective parameters in the Hamiltonian of a dipolar magnetic system is described. The anisotropy of the Hamiltonian is examined for crystal structures ...
  • Diamagnetic susceptibility of a dense electron gas 

    Vignale, G., M. Rosolt, and D. J. W. Geldart. 1988. "Diamagnetic susceptibility of a dense electron gas." Physical Review B (Condensed Matter) 37(5): 2502-7. Copyright © 1988 American Physical Society.
    The authors calculate the diamagnetic susceptibility of a uniform interacting electron gas in the random-phase approximation. From this the exact high-density expansion of the diamagnetic susceptibility is obtained
  • Exact Electron-Gas Response Functions at High-Density - Comment 

    RASOLT, M., and DJW GELDART. 1988. "Exact Electron-Gas Response Functions at High-Density - Comment." Physical Review Letters 60(19): 1983-1983. Copyright © 1988 American Physical Society.
    No abstract available.
  • Comment on `Exact electron-gas response functions at high density' 

    Rasolt, M., D. J. W. Geldart, D. C. Langreth, and S. H. Vosko. 1988. "Comment on `Exact electron-gas response functions at high density'." Physical Review Letters 60(19): 1983-4. Copyright © 1988 American Physical Society.
    For original paper see D.C. Langreth and S.H. Vosko, ibid., vol.59, p.497 (1987). Langreth and Vosko calculated correlation contributions to the Hohenberg-Kohn energy response function Kxc(q,k). They claimed that the results ...
  • Critical magnetic susceptibility of gadolinium 

    Hargraves, P., R. A. Dunlap, D. J. W. Geldart, and S. P. Ritcey. 1988. "Critical magnetic susceptibility of gadolinium." Physical Review B (Condensed Matter) 38(4): 2862-4. Copyright © 1988 American Physical Society.
    The magnetic suspectibility of a single crystal of high-purity gadolinium has been measured in the critical region with use of AC susceptibility methods. For reduced temperatures t10-3, the data are described by a simple ...
  • Critical behavior of two-dimensional magnetic systems with dipole-dipole interactions 

    De'Bell, K., and D. J. W. Geldart. 1989. "Critical behavior of two-dimensional magnetic systems with dipole-dipole interactions." Physical Review B (Condensed Matter) 39(1): 743-4. Copyright © 1989 American Physical Society.
    The critical exponents of two-dimensional dipolar magnetic systems with isotropic in-plane ordering may be obtained from the expansion which determines the exponents of isotropic three-dimensional dipolar systems. However, ...
  • Anisotropy of the critical magnetic susceptibility of gadolinium 

    Geldart, D. J. W., P. Hargraves, N. M. Fujiki, and R. A. Dunlap. 1989. "Anisotropy of the critical magnetic susceptibility of gadolinium." Physical Review Letters 62(23): 2728-31. Copyright © 1989 American Physical Society.
    The magnetic susceptibility along the c axis (xc) and in the basal plane (xb) has been measured on a single crystal of Gd in the reduced temperature range 410-4t1.310-2. Uniaxial anisotropy is observed. Magnetic dipole-dipole ...
  • Plasmons in disordered, two-component, quasi-two-dimensional electron systems 

    Shegelski, M. R. A., and D. J. W. Geldart. 1989. "Plasmons in disordered, two-component, quasi-two-dimensional electron systems." Physical Review B (Condensed Matter) 40(6): 3647-51. Copyright © 1989 American Physical Society.
    The authors investigate the effect of elastic scattering of electrons on the properties of plasmons in a disordered, two-component, quasi-two-dimensional electron gas. Numerical results are given for dispersion relations ...
  • Quantum-Mechanical Interpretation of the Exchange-Correlation Potential of Kohn-Sham Density-Functional Theory - Comment 

    RASOLT, M., and DJW GELDART. 1990. "Quantum-Mechanical Interpretation of the Exchange-Correlation Potential of Kohn-Sham Density-Functional Theory - Comment." Physical Review Letters 65(2): 276-276. Copyright © 1990 American Physical Society.
    No abstract available.
  • Comment on `Quantum-mechanical interpretation of the exchange-correlation potential of Kohn-Sham density-functional theory' 

    Rasolt, M., D. J. W. Geldart, M. K. Harbola, and V. Sahni. 1990. "Comment on `Quantum-mechanical interpretation of the exchange-correlation potential of Kohn-Sham density-functional theory'." Physical Review Letters 65(2): 276-7. Copyright © 1990 American Physical Society.
    For original paper see M.K. Harbola and V. Sahni, ibid., vol.62, p.489 (1989). Harbola and Sahni suggested a procedure for constructing the exchange-correlation potential that enters the Kohn-Sham single-particle equations. ...
  • Short-distance expansion for the spin-spin correlation function of uniaxial dipolar systems 

    Fujiki, N. M., K. De'Bell, and D. J. W. Geldart. 1992. "Short-distance expansion for the spin-spin correlation function of uniaxial dipolar systems." Physical Review B (Condensed Matter) 45(9): 4686-94. Copyright © 1992 American Physical Society.
    Motivated by recent work on the critical resistivity of gadolinium, a detailed study has been made of the temperature dependence of the two-point vertex function in the large-momentum regime. The operator-project expansion ...