Yeong E. Kim

Time-dependent density-functional theory for trapped strongly interacting fermionic atoms

The dynamics of strongly interacting trapped dilute two-component Fermi gases (dilute in the sense that the range of interatomic potential is small compared with interparticle spacing ) is investigated in a single-equation approach to the time-dependent density-functional theory. For the ground-state energy per particle of the system in the homogeneous phase, we have constructed an Pade parametrization based on Monte Carlo data and asymptotic behavior. Our numerical results for collective frequencies in the BCS-BEC crossover regime are in good agreement with recent experimental data obtained by the Duke University group. In addition, we show that the calculated corrections to the hydrodynamic approximation may be important, even for systems with a rather large number of atoms. DOI: 10.1103/PhysRevA.70.033612 PACS number(s): 03.75.Ss, 67.40.Db The recently reported ultracold trapped Fermi gases with tunable atomic scattering length [1‐11] in the vicinity of a Feshbach resonance stimulated a large number of theoretical investigations. Some of these works are based on the assumption that the properties of strongly interacting dilute Fermi gas at zero temperature are well described by the hydrodynamic approximation (HA )[ 12‐15] ]n ]t + „ W · snv Wd =0 , s1d

Theory of Bose–Einstein condensation mechanism for deuteron-induced nuclear reactions in micro/nano-scale metal grains and particles

Recently, there have been many reports of experimental results which indicate occurrences of anomalous deuteron-induced nuclear reactions in metals at low energies. A consistent conventional theoretical description is presented for anomalous low-energy deuteron-induced nuclear reactions in metal. The theory is based on the Bose–Einstein condensate (BEC) state occupied by deuterons trapped in a micro/nano-scale metal grain or particle. The theory is capable of explaining most of the experimentally observed results and also provides theoretical predictions, which can be tested experimentally. Scalabilities of the observed effects are discussed based on theoretical predictions.

Density-functional theory of bosons in a trap

A time-dependent Kohn-Sham-(KS-)like theory is presented for N bosons in three- and lower-dimensional traps. We derive coupled equations, which allow us to calculate the energies of elementary excitations. A rigorous proof is given to show that the KS-like equation correctly describes the properties of one-dimensional impenetrable bosons in a general time-dependent harmonic trap in the large-N limit.

Ground state of charged bosons confined in a harmonic trap

We study a system composed of N identical charged bosons confined in a harmonic trap. Upper and lower energy bounds are given. It is shown in the large N limit that the ground-state energy is determined within an accuracy of

MIXTURES OF CHARGED BOSONS CONFINED IN HARMONIC TRAPS AND BOSE–EINSTEIN CONDENSATION MECHANISM FOR LOW-ENERGY NUCLEAR REACTIONS AND TRANSMUTATION PROCESSES IN CONDENSED MATTERS

\pm 8%

Nuclear Fusion for Bose Nuclei Confined in Ion Traps

and that the mean field theory provides a reasonable result with relative error of less than 16% for the binding energy .

Dynamics of strongly interacting Fermi gases of atoms in a harmonic trap

A mixture of two different species of positively charged bosons in harmonic traps is considered in the mean-field approximation. It is shown that depending on the ratio of parameters, the two components may coexist in same regions of space, in spite of the Coulomb repulsion between the two species. Application of this result is discussed for the generalization of the Bose–Einstein condensation mechanism for low-energy nuclear reaction (LENR) and transmutation processes in condensed matters. For the case of deutron–lithium (d + Li) LENR, the result indicates that (d + 6Li) reactions may dominate over (d + d) reactions in LENR experiments.

Equivalent linear two-body method for many-body problems

Abstract Nuclear fusion of integer spin nuclei confined in an isotropic ion trap is investigated. Solutions of the ground state for charged bosons trapped in the isotropic harmonic oscillator potential are calculated using the equivalent linear two-body method for many-body problems, which is based on an approximate reduction of the many-body Schrödinger equation by the use of a variational principle. Using the ground-state wave function, theoretical estimates of probabilities and rates for nuclear fusion for Bose nuclei confined in ion traps are obtained. Numerical estimates for fusion rates are presented for the case of deuteron-deuteron fusion.

Effect of a Generalized Particle Momentum Distribution on Plasma Nuclear Fusion Rates

Dynamics of strongly interacting trapped dilute Fermi gases is investigated at zero temperature. As an example of application we consider the expansion of the cloud of fermions initially confined in an anisotropic harmonic trap, and study the equation of state dependence of the radii of the trapped cloud and the collective oscillations in the vicinity of a Feshbach resonance.

Collective excitations of strongly interacting Fermi gases of atoms in a harmonic trap

We present a detailed description of the equivalent linear two-body method for the many-body problem, which is based on an approximate reduction of the many-body Schrodinger equation by the use of a variational principle. The method has been applied to the one-dimensional N -body problem with pair-wise contact interactions (McGurie-Yang N -body problem) and to the dilute Bose-Einstein condensation of atoms in harmonic traps at zero temperature for both positive and negative scattering lengths. The ground state energy and wavefunction for a dilute Bose gas are obtained analytically for large value of N and it is shown that the method gives excellent results in the large-N limit.