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We study dynamical phase transitions from antiferromagnetic to paramagnetic states driven by an interaction quench in the fermionic Hubbard model using the nonequilibrium dynamical mean-field theory. We identify two dynamical transition points where the relaxation behavior qualitatively changes: one corresponds to the thermal phase transition at which the order parameter decays critically slowly in a power law ∝t-1/2, and the other is connected to the existence of nonthermal antiferromagnetic order in systems with effective temperature above the thermal critical temperature. The frequency of the amplitude mode extrapolates to zero as one approaches the nonthermal (quasi)critical point, and thermalization is significantly delayed by the trapping in the nonthermal state. A slow relaxation of the nonthermal order is followed by a faster thermalization process. [ABSTRACT FROM AUTHOR]

Intertwined orders exist ubiquitously in strongly correlated electronic systems and lead to intriguing phenomena in quantum materials. In this Letter, we explore the unique opportunity of manipulating intertwined orders through entangling electronic states with quantum light. Using a quantum Floquet formalism to study the cavity-mediated interaction, we show the vacuum fluctuations effectively enhance the charge-density-wave correlation, giving rise to a phase with entangled electronic order and photon coherence, with putative superradiant behaviors in the thermodynamic limit. Furthermore, upon injecting even one single photon in the cavity, different orders, including s-wave and η-paired superconductivity, can be selectively enhanced. Our study suggests a new and generalizable pathway to control intertwined orders and create light-matter entanglement in quantum materials. The mechanism and methodology can be readily generalized to more complicated scenarios. [ABSTRACT FROM AUTHOR]

Autoionizing Rydberg states of molecular N2 are studied using time-, energy-, and angular-resolved photoelectron spectroscopy. A femtosecond extreme ultraviolet pulse with a photon energy of 17.5 eV excites the resonance and a subsequent IR pulse ionizes the molecule before the autoionization takes place. The angular-resolved photoelectron spectra depend on pump-probe time delay and allow for the distinguishing of two electronic states contributing to the resonance. The lifetime of one of the contributions is determined to be 14±1 fs, while the lifetime of the other appears to be significantly shorter than the time resolution of the experiment. These observations suggest that the Rydberg states in this energy region are influenced by the effect of interference stabilization and merge into a complex resonance. [ABSTRACT FROM AUTHOR]

Recent experiments demonstrate precise control over coherently excited circular phonon modes using high-intensity terahertz lasers, opening new pathways towards dynamical, ultrafast design of magnetism in functional materials. While the phonon Zeeman effect enables a theoretical description of phonon-induced magnetism, it lacks efficient angular momentum transfer from the phonon to the electron sector. In this work, we put forward a coupling mechanism based on electron-nuclear quantum geometry, with the inverse Faraday effect as a limiting case. This effect is rooted in the phase accumulation of the electronic wave function under a circular evolution of nuclear coordinates. An excitation pulse then induces a transient level splitting between electronic orbitals that carry angular momentum. First-principles simulations on SrTiO_{3} demonstrate that in parts of the Brillouin zone, this splitting between orbitals carrying angular momentum can easily reach 50 meV.