Is there a polaron signature in angle-resolved photoemission of CsPbBr3?

Abstract

The formation of large polarons has been proposed as reason for the high defect tolerance, low mobility, low charge carrier trapping and low nonradiative recombination rates of lead halide perovskites. Recently, direct evidence for large-polaron formation has been reported from a 50% effective mass enhancement in angle-resolved photoemission of CsPbBr3 over theory for the orthorhombic structure. We present in-depth band dispersion measurements of CsPbBr3 and GW calculations which lead to almost identical effective masses at the valence band maximum of 0.203+/-0.016 m0 in experiment and 0.226 m0 in orthorhombic theory. We argue that the effective mass can be explained solely on the basis of electron-electron correlation and large-polaron formation cannot be concluded from photoemission data.

Version 2 contains more precise theoretical values and supplemental material

References in corpus (5)

• Efficient implementation of the GW approximation within the all-electron FLAPW method
• Electron-phonon interaction and charge carrier mass enhancement in SrTiO3
• Slow cooling of hot polarons in halide perovskite solar cells
• Limits to Electrical Mobility in Lead-Halide Perovskite Semiconductors
• Quantifying polaronic effects on charge-carrier scattering and mobility in lead--halide perovskites

Cited by in corpus (3)

• Dark states of electrons in a quantum system with two pairs of sublattices
• Determining Exciton Binding Energy and Reduced Effective Mass in Metal Tri-Halide Perovskites from Optical and Impedance Spectroscopy Measurements
• Spectral function of a bipolaron coupled to dispersive optical phonons