title: Unraveling the Exciton Binding Energy and the Dielectric Constant in Single-Crystal Methylammonium Lead Triiodide Perovskite.
abstract: We have accurately determined the exciton binding energy and reduced mass of single crystals of methylammonium lead triiodide using magneto-reflectivity at very high magnetic fields. The single crystal has excellent optical properties with a narrow line width of ∼3 meV for the excitonic transitions and a 2s transition that is clearly visible even at zero magnetic field. The exciton binding energy of 16 ± 2 meV in the low-temperature orthorhombic phase is almost identical to the value found in polycrystalline samples, crucially ruling out any possibility that the exciton binding energy depends on the grain size. In the room-temperature tetragonal phase, an upper limit for the exciton binding energy of 12 ± 4 meV is estimated from the evolution of 1s-2s splitting at high magnetic field.
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UGA-UPS-INSA, Grenoble and Toulouse 31400, France.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UGA-UPS-INSA, Grenoble and Toulouse 31400, France.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Surrente
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UGA-UPS-INSA, Grenoble and Toulouse 31400, France.|Institute of Experimental Physics, Faculty of Physics, University of Warsaw , Pasteura 5, 02-093 Warsaw, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Galkowski
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UGA-UPS-INSA, Grenoble and Toulouse 31400, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bruyant
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UGA-UPS-INSA, Grenoble and Toulouse 31400, France.
authors.forename: Duncan K
authors.initials: DK
authors.lastname: Maude
authors.affiliation: University of Oxford , Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: Amir Abbas
authors.initials: AA
authors.lastname: Haghighirad
authors.affiliation: University of Oxford , Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Snaith
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UGA-UPS-INSA, Grenoble and Toulouse 31400, France.
authors.forename: Paulina
authors.identifier: http://orcid.org/0000-0002-4019-6138
authors.initials: P
authors.lastname: Plochocka
authors.affiliation: University of Oxford , Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Nicholas