arXiv subjects

Jungsoo Kim

Publications and source records attributed to Jungsoo Kim.

22 records · Page 2Linked to original sources

arXiv2009

Handlebody-preserving finite group actions on Haken manifolds with Heegaard genus two

Let $M$ be a closed orientable 3-manifold with a genus two Heegaard splitting $(V_1, V_2; F)$ and a non-trivial JSJ-decomposition, where all components of the intersection of the JSJ-tori and $V_i$ are not $\partial$-parallel in $V_i$ for $i=1,2$. If $G$ is a finite group of orientation-preserving diffeomorphisms acting on $M$ which preserves each handlebody of the Heegaard splitting and each piece of the JSJ-decomposition of $M$, then $G\cong \mathbb{Z}_2$ or $\mathbb{D}_2$ if $V_j\cap(\cup T_i)$ consists of at most two disks or at most two annuli.

math.GT↗

arXiv2009

Handlebody-preserving finite group actions on Haken manifolds with Heegaard genus two - II

Let $M$ be a closed orientable 3-manifold with a genus two Heegaard splitting $(V_1, V_2; F)$ and a non-trivial JSJ-decomposition, where all components of the intersection of the JSJ-tori and $V_i$ are not $\partial$-parallel in $V_i$ for $i=1,2$. If $G$ is a finite group of orientation-preserving smooth actions on $M$ which preserves each handlebody of the Heegaard splitting and each piece of the JSJ-decomposition of $M$, then $G\cong \mathbb{Z}_2$ or $\mathbb{D}_2$ unless $V_j\cap(\cup T_i)$ has three or more disk components for $j=1$ or 2.

math.GT↗

arXiv1999

Evolution of Fermi Liquid Behavior with Doping in the Hubbard Model

We calculate the single-particle Green's function for the tight-binding band structure, $ξ_{\vec p}=-2t\cos p_x-2t\cos p_y -μ$, with a function of chemical potential $μ$ for square-lattice system. The form of the single-particle self-energy, $Σ({\vec p}, E)$, is determined by the density-density correlation function, $χ({\vec q}, ω)$, which develops two peaks for $μ\gtrsim -2.5t$ unlike parabolic band case. Near half filling $χ({\vec q}, ω)$ becomes independent of $ω$, one dimensional behavior, at intermediate values of $ω$ which leads to one dimensional behavior in $Σ({\vec p},E)$. However $μ\leq -0.1t$ there is no influence on the Fermi Liquid dependences from SDW instability. The strong $\vec p$ and $E$ dependence of the off-shell self-energy, $Σ(p,E)$, found earlier for the parabolic band is recovered for $μ\lesssim -t$ but deviations from this develop for $μ\gtrsim -0.1t$. The resonance peak width of the spectral function, $A({\vec p}, E)$ has linear dependence in $ξ_{\vec p}$ due to the $E$ dependence of the imaginary part of $Σ({\vec p}, E)$. We point out that an accurate detailed form for $Σ({\vec p},E)$ would be very difficult to recover from ARPES data for the spectral density.

cond-mat.str-el↗

arXiv1997

Single-Particle Properties of a Two-Dimensional Fermi Liquid at finite Frequencies and Temperatures

We review the leading momentum, frequency and temperature dependences of the single particle self-energy and the corresponding term in the entropy of a two dimensional Fermi liquid (FL) with a free particle spectrum. We calculate the corrections to these leading dependences for the paramagnon model and the electron gas and find that the leading dependences are limited to regions of energy and temperature which decrease with decreasing number density of fermions. This can make it difficult to identify the frequency and temperature dependent characteristics of a FL ground state in experimental quantities in low density systems even when complications of band structure and other degrees of freedom are absent. This is an important consideration when the normal state properties of the undoped cuprate superconductors are analyzed.

cond-mat.str-el↗