Posted on Authorea 17 May 2021 — The copyright holder is the author/funder. All rights reserved. No reuse without permission. — https://doi.org/10.22541/au.162126579.98860824/v1 — This a preprint and has not been peer reviewed. Data may be preliminary. hrfr,tentr ftelws nrynurlitradectto omn h xio sudrdebate. environment. under is dielectric exciton or the doping forming strain excitation as interband such neutral stimuli conduction energy the external transition lowest in to air-stable the valleys prone two of of and for nature class energy by states the in single-particle caused the Therefore, close The eV is very 0.5 . systems are limit of such band monolayer order MoS the of the approaching e.g., materials. ambassador on when as, material prominent energies bulk (TMDCs) binding most in exciton dichalcogenides The as strong metal the well . of screening as because semiconductors reduced systems two-dimensional studied zero-dimensional thin intensely two-dimensional in ultimately been molecules, in tubes, with has and interaction also light-matter and insulators structure, exciton-dominated fine semiconductors, wires the a Recently, in and one-dimensional exist states can dots, Rydberg Excitons Excitons featuring quantum force. alignment. model, Coulomb light atom spin attractive with hydrogen to by solid solid- the a together respect of of a bound excitation analogues pair in neutral as electron-hole the viewed phenomena photo-excited described be a many-body he molecule. when – describe a 1930 exciton in to an or Frenkel pairs by Y. solid quasiparticles by Cooper a interacting pioneered for was in weakly system e.g., pair the state employing as, electron-hole than of bound boson statistics concept a composite The quasiparticle to a amounts different into latter have fermions The can two phenomena excitons. transforming and emergent and with others e.g. connected ; often or real-particles, quanta are flux superfluidity underlying Quasiparticles describing of superconductivity, quasiparticles . number the solids as even of plasmons, in such an or quasiparticles electrons vibrations, with free – bosons lattice of coupled fermions collective composite excitation electrons of composite the collective are of quasiparticles ; of that the consisting phonons phonons, atoms – – also virtual the states superconductors and of and effect in mass exchange Hall electrons quasiparticles effective by quantum other – coupled an fractional many pairs electrons with by two Cooper electrons surrounded of are by being comprised examples despite described Further vacuum are . in that solid electrons crystals free in of as band-electrons that acting to are quantum-mechanical particles solved examples interacting often The Prominent strongly is of systems involved. problem many-body quasiparticles. are the in interacting transforming particles behavior weakly approach thereby collective many this quasiparticles, and sufficient, and introducing excitations often by stronger elementary is describing become picture of single-particle interactions problem a the While in interactions. when description manifold their by fails determined systems are interacting systems weakly other and for materials solid-state of properties Physical Westf (SoN), [email protected] Nanoscience + Soft for M Center 48149 and Wilhelm-Klemm-Str.10, Physics of Institute space momentum and real Wurstbauer in Ursula dynamics and properties quasiparticle Disclosed: 2021 17, May 1 Wurstbauer Ursula and real in space dynamics momentum and properties quasiparticle Disclosed: nvriyo ¨ntrDprmn fPhysics of M¨unster Department of University 1 ntr Germany. unster, ¨ 2 rWSe or 1 2 httasto rma niett ietgap direct a to indirect an from transition that ¨ lsh Wilhelms-Universit alische ¨ tM at unster, ¨ Posted on Authorea 17 May 2021 — The copyright holder is the author/funder. All rights reserved. No reuse without permission. — https://doi.org/10.22541/au.162126579.98860824/v1 — This a preprint and has not been peer reviewed. Data may be preliminary. yFuirtasomto ftemmnu itiuin elsaeifraino h xioi tt could state another scatter excitonic at the quasiparticles of residing the information state fs space 18 electron real distribution, the about momentum of with the time momentum of a mass transformation Fourier of within of the By population generation fast center - exciton the Rather finite point bright symmetry report with fs. a high ensemble 17 to al. of exciton decay about et vanishing an excitations of have Dong into elementary time particles scheme, neutral dephasing generated excitation The a the the near-resonant within a excitation, polarization. at such resonance excitonic band For coherent near valence For a energy. the 1 the access . the from if little structure of electron just corners fulfilled band the an are the at promote in conditions located transition point to excitation symmetry sufficient Near-resonant high are just -points domain. 1 is dependence the time photon gap in in and characteristics band absorbed -point fundamental photoemission energy the the the the to study of close to in energy energy pulse excitation of probe pulse the XUV pump time-delayed of a a (tr-ARPES) with with spectroscopy [Dong21] excited probed coworkers photoemission first and is angle-resolved and material and Dong The time-resolved WSe measurements. semiconductor through momentum-, invention. layered monitored time-, the quasi-particle was the in access excitons excitons the and directly of after challenging to properties scheme energy-resolved remains years and spectroscopy [Dong21, 90 photoemission a excitons multi-dimensional than wave- momentum of a quasiparticle more employed finite concept the only of complex of The achieved of distribution visualization description states. spatial was direct and the particle and understanding of single [Dong21] the measurement underlying function simplifying direct However, the significantly story of phenomena. success energy-momentum those 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antb naee ysc ehius The techniques. such by unraveled be cannot excitation neutral the describing quasiparticles those of ) st rloi oe(Z otecnuto ada the at band conduction the to (BZ) Zone Brillouin Σ on nieteB n h oesaea the at state hole the and BZ the inside point 2 st Zwt h oeteeg ietinterband direct energy lowest the with BZ K pitlaigahl eid The behind. hole a leaving -point K 2 pita h onro h BZ. the of corner the at -point Tedcydnmc fbright of dynamics decay .The k K K - Posted on Authorea 17 May 2021 — The copyright holder is the author/funder. All rights reserved. No reuse without permission. — https://doi.org/10.22541/au.162126579.98860824/v1 — This a preprint and has not been peer reviewed. Data may be preliminary. hsb xetdt dac u urn nesadn fitrcindie mretpeoeai solid in phenomena can emergent [Dong21] interaction-driven [Dong21] al. of et understanding Dong as current by our serve introduced know systems. advance method might to state to the enable beneficial that of expected highly effects excitons extension be be hybridization would The direct thus high selective it and properties. quantum-circuitries, Valley at mechanical realistic excitons quantum into phenomena charge . integration their For correlation nature of . emergent switching bosonic qubits show gate-tunable their quasiparticle hence to to due and expected the electric-field temperatures ensembles. are of dense low distribution quasiparticles wave-functions, thermalized and spatial single-particle of bosonic densities underlying formation the of the the uncover Among allow ensembles of also interest. that overlap of to Such lifetimes reduced states enhanced promise to exhibit many-body the Due excitons other holds charge-transfer of excitons. valued. properties charge-transfer al. expected distinct are et theoretically the these Dong the with of with along an method wavefunction consistent and quasiparticle is the determined which is future, obtained, envelope the is function In wave nm quasiparticle 1.78 isotropic of the radius way, Bohr this exciton In [Dong21]. extracted be 3