C: Hartree—Fock self-energies at zero temperature

Local magnetic moments of Fe 1/ Cr N inclusions in an Fe matrix are calculated as a function of the Cr number of atoms N at zero temperature, and for N ≤ 64. We use a realistic spd-band Hamiltonian to determine their magnetic properties. The local magnetic moments μ(i) at the various cluster sites i are calculated self-consistently in the unrestricted Hartree–Fock approximation. The matrix Fe atoms couple always antiferromagnetically with the Cr atoms. The μ(i) of Cr atoms at the interface are enhanced by the presence of Fe atoms in their first nearest neighbor shell. In most cases the Fe moments close to the cluster are reduced. A remarkable interplay between the antiferromagnetism of Cr and the ferromagnetism of Fe is obtained.

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Some consequences of the thermal Hartree-Fock approximation at zero temperature

Annals of Physics ◽

10.1016/0003-4916(67)90122-4 ◽

1967 ◽

Vol 45 (2) ◽

pp. 186-190 ◽

Cited By ~ 14

Author(s):

J Sokoloff

Keyword(s):

Zero Temperature ◽

Hartree Fock

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Some consequences of the thermal Hartree-Fock approximation at zero temperature

Annals of Physics ◽

10.1016/0003-4916(67)90324-7 ◽

1967 ◽

Vol 45 (1) ◽

pp. 164

Keyword(s):

Zero Temperature ◽

Hartree Fock

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ORBITALLY STABLE STATES IN GENERALIZED HARTREE–FOCK THEORY

Mathematical Models and Methods in Applied Sciences ◽

10.1142/s0218202509003450 ◽

2009 ◽

Vol 19 (03) ◽

pp. 347-367 ◽

Cited By ~ 7

Author(s):

JEAN DOLBEAULT ◽

PATRICIO FELMER ◽

MATHIEU LEWIN

Keyword(s):

Orbital Stability ◽

Stability Result ◽

Temperature Limit ◽

Total Charge ◽

Zero Temperature ◽

Stable States ◽

Large Classes ◽

Energy Functionals ◽

Hartree Fock ◽

The Cauchy Problem

This paper is devoted to a generalized Hartree–Fock model in the Euclidean space. For large classes of free energy functionals, minimizers are obtained as long as the total charge of the system does not exceed a threshold which depends on a parameter that we call the temperature in analogy with models based on a thermodynamical approach. The usual Hartree–Fock model is recovered in the zero temperature limit. An orbital stability result for the Cauchy problem is deduced from the variational approach.

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NONLINEAR SCHRÖDINGER EQUATION FOR SUPERCONDUCTORS

Modern Physics Letters B ◽

10.1142/s021798499500070x ◽

1995 ◽

Vol 09 (11n12) ◽

pp. 755-761 ◽

Cited By ~ 14

Author(s):

PING AO ◽

DAVID J. THOULESS ◽

X.-M. ZHU

Keyword(s):

Schrödinger Equation ◽

Vortex Dynamics ◽

Schrodinger Equation ◽

Zero Temperature ◽

Galilean Invariance ◽

Josephson Effects ◽

Hartree Fock ◽

Oppenheimer Approximation ◽

Unified Description ◽

Superconducting Condensate

Using the Hartree–Fock–Bogoliubov factorization of the density matrix and the Born–Oppenheimer approximation we show that the motion of a superconducting condensate satisfies a Schrödinger equation at zero temperature. The Galilean invariance of the equation is explicitly manifested. This equation gives a unified description of the condensate dynamics, such as Josephson effects, vortex dynamics and the Bogoliubov–Anderson mode.

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Persistent Currents in Continuous One-Dimensional Disordered Rings within the Hartree–Fock Approximation

International Journal of Modern Physics B ◽

10.1142/s0217979297000964 ◽

1997 ◽

Vol 11 (15) ◽

pp. 1845-1863 ◽

Cited By ~ 5

Author(s):

A. Cohen ◽

R. Berkovits ◽

A. Heinrich

Keyword(s):

Energy Levels ◽

Tight Binding ◽

Zero Temperature ◽

Persistent Currents ◽

One Dimensional ◽

Hartree Fock ◽

Self Consistent ◽

Binding Models ◽

Interacting Electrons ◽

Disorder Potential

We present numerical results for the zero temperature persistent currents carried by interacting spinless electrons in disordered one-dimensional continuous rings. The disorder potential is described by a collection of δ-functions at random locations and strengths. The calculations are performed by a self-consistent Hartree–Fock (HF) approximation. Because the HF approximation retains the concept of single-electron levels, we compare the statistics of energy levels of noninteracting electrons with those of interacting electrons as well as of the level persistent currents. We find that the e–e interactions alter the levels and samples persistent currents and introduces a preffered diamagnetic current direction. In contrast to the analogous calculations that recently appeared in the literature for interacting spinless electrons in the presence of moderate disorder in tight-binding models we find no suppression of the persistent currents due to the e–e interactions.

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Macroscopic Squeezing in Bose–Einstein Condensate

Modern Physics Letters B ◽

10.1142/s0217984998000822 ◽

1998 ◽

Vol 12 (18) ◽

pp. 705-713 ◽

Cited By ~ 11

Author(s):

Patric Navez

Keyword(s):

Ground State ◽

Particle Number ◽

Einstein Condensate ◽

Condensed State ◽

Zero Temperature ◽

Hartree Fock ◽

Bose Einstein Condensate ◽

Normal Behavior ◽

Particle Number Conservation ◽

Bose Einstein

We study the ground state of a uniform Bose gas at zero temperature in the Hartree–Fock–Bogoliubov (HFB) approximation. We find a solution of the HFB equations which obeys the Hugenholtz–Pines theorem. This solution imposes a macroscopic squeezing to the condensed state and as a consequence displays large particle number fluctuations. Particle number conservation is restored by building the appropriate U(1) invariant ground state via the superposition of the squeezed states. The condensed particle number distribution of this new ground state is calculated as well as its fluctuations which present a normal behavior.

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