156 citations · 668 across the 23 of their papers we have counts for
7 papers · 1 filter
Insights into the Electron-Electron Interaction from Quantum Monte Carlo Calculations
Carl A. Kukkonen, Kun Chen
The effective electron-electron interaction in the electron gas depends on both the density and spin local field factors. Variational Diagrammatic Quantum Monte Carlo calculations…
Fermionic Sign Structure of High-order Feynman diagrams in a Many-fermion System
Bao-Zong Wang, Peng-Cheng Hou, Youjin Deng +2
The sign cancellation between scattering amplitudes makes fermions different from bosons. We systematically investigate Feynman diagrams' fermionic sign structure in a representati…
Even-Odd effect of an Spin-S impurity coupled to a quantum critical system
Kun Chen, Yashar Komijani
We discuss an even-odd effect for an impurity with an -fold degenerate internal states immersed in a two-dimensional superfluid--Mott-insulator quantum critical bath, which is d…
The halon: a quasiparticle featuring critical charge fractionalization
Kun Chen, Yuan Huang, Youjin Deng +1
The halon is a special critical state of an impurity in a quantum-critical environment. The hallmark of the halon physics is that a well-defined integer charge gets fractionalized…
Trapping Collapse
Kun Chen, Nikolay V. Prokof'ev, Boris V. Svistunov
Weak potential wells (or traps) in one and two dimensions, and the potential wells slightly deeper than the critical ones in three dimensions, feature shallow bound states with loc…
Trapping Centers at the Superfluid-Mott-insulator Criticality: Transition between Charge-quantized States
Yuan Huang, Kun Chen, Youjin Deng +1
Under the conditions of superfluid-Mott-insulator criticality in two dimensions, the trapping centers--i.e., local potential wells and bumps--are generically characterized by an in…
The Massive Goldstone (Higgs) mode in two-dimensional ultracold atomic lattice systems
Longxiang Liu, Kun Chen, Youjin Deng +3
We discuss how to reveal the massive Goldstone mode, often referred to as the Higgs amplitude mode, near the Superfluid-to-Insulator quantum critical point (QCP) in a system of two…