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Pair correlated atoms in ultracold fermi gas. / 超低溫費米氣體中的對關聯粒子 / Pair correlated atoms in ultracold fermi gas. / Chao di wen fei mi qi ti zhong de dui guan lian li ziJanuary 2007 (has links)
Pong, Yue Hin = 超低溫費米氣體中的對關聯粒子 / 龐宇軒. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 77-81). / Text in English, abstracts in English and Chinese. / Pong, Yue Hin = Chao di wen fei mi qi ti zhong de dui guan lian li zi / Pang Yuxuan. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Review on BCS theory --- p.4 / Chapter 2.1 --- BCS in uniform gas --- p.4 / Chapter 2.2 --- Hartree Fock Bogoliubov equations --- p.7 / Chapter 2.3 --- Regularization techniques --- p.13 / Chapter 2.4 --- Homogeneous solution to HFB --- p.15 / Chapter 3 --- HFB Computation --- p.17 / Chapter 3.1 --- Example: 1D infinite well --- p.18 / Chapter 3.2 --- Example: 1D SHO --- p.22 / Chapter 3.3 --- Example: Spherical harmonic oscillator --- p.23 / Chapter 3.4 --- Conclusion --- p.26 / Chapter 4 --- Natural Orbits --- p.28 / Chapter 4.1 --- Two-point correlation functions --- p.29 / Chapter 4.2 --- Connection with the BCS --- p.32 / Chapter 4.3 --- Natural orbits in a spherical harmonic potential --- p.33 / Chapter 4.4 --- Remarks --- p.38 / Chapter 5 --- Bosonic characters of atomic Cooper pairs across resonance --- p.43 / Chapter 5.1 --- Resonance in Fermi gas --- p.44 / Chapter 5.2 --- Bosonic tests --- p.50 / Chapter 5.3 --- Choosing a Cooper pair wave function --- p.52 / Chapter 5.3.1 --- Cooper pair I --- p.52 / Chapter 5.3.2 --- Cooper pair II --- p.55 / Chapter 5.4 --- Results in a uniform gas --- p.55 / Chapter 5.5 --- Remark --- p.61 / Chapter 6 --- Time dependent BCS: A numerical study --- p.63 / Chapter 6.1 --- Time evolution in uniform BCS --- p.64 / Chapter 6.2 --- Perturbation to interaction strength --- p.66 / Chapter 6.2.1 --- Sudden decrease in the interaction strength --- p.66 / Chapter 6.2.2 --- Sinusoidal variation of interaction strength --- p.68 / Chapter 6.2.3 --- A decaying energy gap --- p.69 / Chapter 6.3 --- Perturbation to particle numbers --- p.71 / Chapter 6.4 --- Remarks --- p.74 / Chapter 7 --- Summary and Outlook --- p.75 / Chapter 7.1 --- Outlook --- p.75 / Bibliography --- p.77 / Chapter A --- Analytic solutions to homogeneous BCS --- p.82 / Chapter B --- Local Density Approximation (LDA) --- p.84 / Chapter B.1 --- One dimensional LDA --- p.85 / Chapter C --- Finding the regularized Green's Function --- p.87 / Chapter D --- Variational approach to finding natural orbits --- p.90 / Chapter D.1 --- Variation with respect to natural orbits --- p.90 / Chapter D.2 --- Variation with respect to the occupation amplitude --- p.93
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The unitary Fermi gas /Drut, Joaquín E. January 2008 (has links)
Thesis (Ph. D.)--University of Washington, 2008. / Vita. Includes bibliographical references (p. 82-91).
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Effect of screening on an ion moving in an electron gasDas, A. K. January 1966 (has links)
No description available.
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Two-particle excitations in random mediaUldry, Anne-Christine January 2002 (has links)
No description available.
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The kondo screening cloudPanos, Brandon Leigh January 2017 (has links)
A dissertation submitted in fulfillment of the requirements for the degree of
Master of Science in Physics
at
the University of the Witwatersrand. November 7th, 2016 / The spin-1=2 Kondo model describes an antiferromagnetic exchange
interaction between an impurity spin and the spin-density of a Fermi gas.
Although the thermodynamics of this system have been resolved, there are
still some unanswered questions regarding its spatial features. The spatial
region of correlation between the impurity spin and the spin-density of
the Fermi gas is referred to as the Kondo screening cloud. For the case of
anisotropic couplings, the cloud consists of four distinct components. In
this dissertation we use the bosonization technique to derive both an exact
numeric and an approximate analytic expression for the forward scattering
longitudinal cloud at the Toulouse point. The expressions are then extended
to incorporate the effects of a time-independent external magnetic field. The
non-magnetic case displays universal scaling behavior, while the addition
of an external magnetic field only slightly spoils the scaling in the vicinity
of the crossover length (B)
K , but remarkably not deep inside or outside the
cloud. / MT2017
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Low-dimensional Fermi gases : from few to many-body physicsNgampruetikorn, Vudtiwat January 2015 (has links)
No description available.
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Impurities in a homogeneous electron gasSong, Jung-Hwan 07 December 2004 (has links)
Immersion energies for an impurity in a homogeneous electron gas with a uniform
positive background charge density have been calculated numerically using
density functional theory. The numerical aspects of this problem are very demanding
and have not been properly discussed in previous work. The numerical
problems are related to approximations of infinity and continuity, and they have
been corrected using physics based on the Friedel sum rule and Friedel oscillations.
The numerical precision is tested extensively. Immersion energies are obtained for
non-spin-polarized systems, and are compared with published data. Numerical
results, such as phase shifts, density of states, dielectric constants, and compressibilities, are obtained and compared with analytical theories. Immersion energies
for excited systems are obtained by varying the number of electrons in the bound
states of an impurity. The model is extended to spin-polarized systems and is
tested in detail for a carbon impurity. The spin-coupling with an external magnetic
field is considered mainly for a hydrogen impurity. These new results show
very interesting behavior at low densities. / Graduation date: 2005
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Collective phenomena in ultracold Fermi gasesEdge, Jonathan Martin January 2011 (has links)
No description available.
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Collective modes and polarons in two-dimensional fermi gasesVogt, Enrico January 2013 (has links)
No description available.
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Spin polarised Fermi gasesSadeghzadeh, Kayvan January 2012 (has links)
No description available.
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