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This corrects the article DOI: 10.1103/PhysRevLett.120.166401.

Strongly correlated materials exhibit intriguing properties caused by intertwined microscopic interactions that are hard to disentangle in equilibrium. Employing nonequilibrium time-resolved photoemission spectroscopy on the quasi-two-dimensional transition-metal dichalcogenide $1T$-$\mathrm{Ta}{\mathrm{S}}_{2}$, we identify a spectroscopic signature of doubly occupied sites (doublons) that reflects fundamental Mott physics. Doublon-hole recombination is estimated to occur on timescales of electronic hopping $\ensuremath{\hbar}/J\ensuremath{\approx}14\text{ }\text{ }\mathrm{fs}$. Despite strong electron-phonon coupling, the dynamics can be explained by purely electronic effects captured by the single-band Hubbard model under the assumption of weak hole doping, in agreement with our static sample characterization. This sensitive interplay of static doping and vicinity to the metal-insulator transition suggests a way to modify doublon relaxation on the few-femtosecond timescale.

Strongly correlated materials exhibit intriguing properties caused by intertwined microscopic interactions that are hard to disentangle in equilibrium. Employing nonequilibrium time-resolved photoemission spectroscopy on the quasi-two-dimensional transition-metal dichalcogenide 1T-TaS_{2}, we identify a spectroscopic signature of doubly occupied sites (doublons) that reflects fundamental Mott physics. Doublon-hole recombination is estimated to occur on timescales of electronic hopping ℏ/J≈14 fs. Despite strong electron-phonon coupling, the dynamics can be explained by purely electronic effects captured by the single-band Hubbard model under the assumption of weak hole doping, in agreement with our static sample characterization. This sensitive interplay of static doping and vicinity to the metal-insulator transition suggests a way to modify doublon relaxation on the few-femtosecond timescale.

Femtosecond time-resolved core-level photoemission spectroscopy with a free-electron laser is used to measure the atomic-site specific charge-order dynamics of the charge-density wave in the Mott insulator 1T-TaS2. After strong photoexcitation, a prompt loss of charge order and subsequent fast equilibration dynamics of the electron-lattice system are observed. On the time scale of electron-phonon thermalization, about 1 ps, the system is driven across a phase transition from a long-range charge ordered state to a quasiequilibrium state with domainlike short-range charge and lattice order. The experiment opens the way to study the nonequilibrium dynamics of condensed matter systems with full elemental, chemical, and atomic-site selectivity.

Photoemission microspectroscopy on the layered misfit compound $(\mathrm{PbS}{)}_{1.13}{\mathrm{TaS}}_{2}$ provides direct evidence for Ta substitution into PbS layers as well as for Pb substitution into ${\mathrm{TaS}}_{2}$ layers. This metal cross substitution alters the charge balance between alternating layers and can explain the remarkable stability of $(\mathrm{PbS}{)}_{1.13}{\mathrm{TaS}}_{2}$ and, possibly, of analogous misfit compounds. It is suggested that even formally stoichiometric misfit compounds can be stabilized by this mechanism.