183 citations · 614 across the 26 of their papers we have counts for
24 papers · 1 filter
Quantics tensor cross interpolation for high-order strong-coupling expansions
Kanghyeon Kim, Lei Geng, Philipp Werner +1
Real-time impurity solvers enable the study of transport phenomena and the description of nonequilibrium lattice systems within the framework of dynamical mean-field theory (DMFT).…
-pairing in metallic and particle-hole asymmetric systems
Philipp Werner, Aaram J. Kim, Lei Geng
Light-induced superconducting-like states have been reported in several classes of correlated materials. From a theoretical point of view, the induction of -pairing is a promisi…
High-temperature -pairing superconductivity in the photodoped Hubbard model
Lei Geng, Aaram J. Kim, Philipp Werner
We investigate superconductivity emerging in the photodoped Mott insulating Hubbard model using steady-state dynamical mean-field theory implemented on the real-frequency axis. By…
Strange diffusivity of incoherent metal in half-filled two-dimensional Hubbard model
Youngmin Eom, Igor S. Tupitsyn, Nikolay V. Prokof'ev +3
We study charge transport across the metal-insulator crossover in the half-filled two-dimensional Hubbard model, with particular emphasis on precision control. The dynamic current-…
Third-order strong-coupling impurity solver for real-frequency DMFT: Accurate spectral functions for antiferromagnetic and photo-doped states
Lei Geng, Aaram J. Kim, Philipp Werner
We present a real-frequency third-order strong-coupling impurity solver which employs quantics tensor cross interpolation (QTCI) for an efficient evaluation of the diagram weights.…
Strong coupling impurity solver based on quantics tensor cross interpolation
Aaram J. Kim, Philipp Werner
Numerical methods capable of handling nonequilibrium impurity models are essential for the study of transport problems and the solution of the nonequilibrium dynamical mean field t…
Misleading convergence of the skeleton diagrammatic technique: when the correct solution can be found
Aaram J. Kim, Evgeny Kozik
Convergence of the self-consistent skeleton diagrammatic technique (SDT) -- in which the full Green's function is determined through summation of Feynman diagrams in terms of itsel…
Pseudoparticle vertex solver for quantum impurity models
Aaram J. Kim, Jiajun Li, Martin Eckstein +1
We present a quantum impurity solver based on a pseudo-particle framework, which combines diagrammatic resummations for a three-point vertex with diagrammatic Monte Carlo sampling…
Twisted chiral superconductivity in photodoped frustrated Mott insulators
Jiajun Li, Markus Müller, Aaram J. Kim +2
Recent advances in ultrafast pump-probe spectroscopy provide access to hidden phases of correlated matter, including light-induced superconducting states, but the theoretical under…
Vertex-based Diagrammatic Treatment of Light-Matter-Coupled Systems
Aaram J. Kim, Katharina Lenk, Jiajun Li +2
We propose a diagrammatic Monte Carlo approach for general spin-boson models, which can be regarded as a generalization of the strong-coupling expansion for fermionic impurity mode…
Evaluating second-order phase transitions with Diagrammatic Monte Carlo: Néel Transition in the doped three-dimensional Hubbard model
Connor Lenihan, Aaram J. Kim, Fedor Šimkovic IV. +1
Diagrammatic Monte Carlo -- the technique for numerically exact summation of all Feynman diagrams to high orders -- offers a unique unbiased probe of continuous phase transitions.…
Strange Metal Solution in the Diagrammatic Theory for the Hubbard Model
Aaram J. Kim, Philipp Werner, Evgeny Kozik
We show that the numerically exact bold-line diagrammatic theory for the Hubbard model exhibits a non-Fermi-liquid (NFL) strange metal state, which is connected to the SYK NFL…
Homotopic Action: A Pathway to Convergent Diagrammatic Theories
Aaram J. Kim, Nikolay V. Prokof'ev, Boris V. Svistunov +1
The major obstacle preventing Feynman diagrammatic expansions from accurately solving many-fermion systems in strongly correlated regimes is the series slow convergence or divergen…
Tracking the Footprints of Spin Fluctuations: A MultiMethod, MultiMessenger Study of the Two-Dimensional Hubbard Model
Thomas Schäfer, Nils Wentzell, Fedor Šimkovic +23
The Hubbard model represents the fundamental model for interacting quantum systems and electronic correlations. Using the two-dimensional half-filled Hubbard model at weak coupling…
Entropy in the non-Fermi-liquid regime of the doped Hubbard model
Connor Lenihan, Aaram J. Kim, Fedor Šimkovic IV. +1
We study thermodynamic properties of the doped Hubbard model on the square lattice in the regime of strong charge and spin fluctuations at low temperatures near the metal-to-insula…
Alleviating the Sign Problem in Quantum Monte Carlo Simulations of Spin-Orbit-Coupled Multi-Orbital Hubbard Models
Aaram J. Kim, Philipp Werner, Roser Valentí
We present a strategy to alleviate the sign problem in continuous-time quantum Monte Carlo (CTQMC) simulations of the dynamical-mean-field-theory (DMFT) equations for the spin-orbi…
Spin and charge correlations across the metal-to-insulator crossover in the half-filled Hubbard model
Aaram J. Kim, Fedor Simkovic, Evgeny Kozik
The Hubbard model with nearest-neighbour hopping on the square lattice and an average of one electron per site is known to undergo an extended crossover from metallic to insul…
Multi-valuedness of the Luttinger-Ward functional in the Fermionic and Bosonic System with Replicas
Aaram J. Kim, Vincent Sacksteder
We study the properties of the Luttinger-Ward functional (LWF) in a simplified Hubbard-type model without time or spatial dimensions, but with identical replicas located on a s…
Extended crossover from Fermi liquid to quasi-antiferromagnet in the half-filled 2D Hubbard model
Fedor Šimkovic, J. P. F. LeBlanc, Aaram J. Kim +4
The ground state of the Hubbard model with nearest-neighbor hopping on the square lattice at half filling is known to be that of an antiferromagnetic (AFM) band insulator for any o…
Spin freezing and the Sachdev-Ye model
Philipp Werner, Aaram Kim, Shintaro Hoshino
Spin-freezing is the origin of bad-metal physics and non-Fermi liquid (non-FL) properties in a broad range of correlated compounds. In a multi-orbital lattice system with Hund coup…
Hubbard band or oxygen vacancy states in the correlated electron metal SrVO?
S. Backes, T. C. Rödel, F. Fortuna +19
We study the effect of oxygen vacancies on the electronic structure of the model strongly correlated metal SrVO. By means of angle-resolved photoemission (ARPES) synchrotron ex…
Slope-Reversed Mott Transition in Multiorbital Systems
Aaram J. Kim, MooYoung Choi, Gun Sang Jeon
We examine finite-temperature phase transitions in the two-orbital Hubbard model with different bandwidths by means of the dynamical mean-field theory combined with the continuous-…
Estimate of the Phase Transition Line in the Infinite-dimensional Hubbard Model
Aaram J. Kim, M. Y. Choi, Gun Sang Jeon
We consider a Mott transition of the Hubbard model in infinite dimensions. The dynamical mean- field theory is employed in combination with a continuous-time quantum Monte Carlo (C…
Finite-temperature phase transitions in the ionic Hubbard model
Aaram J. Kim, M. Y. Choi, Gun Sang Jeon
We investigate paramagnetic metal-insulator transitions in the infinite-dimensional ionic Hubbard model at finite temperatures. By means of the dynamical mean-field theory with an…