Author(s): Chen, YD (Chen, Yingda); Zhang, D (Zhang, Dong); Chang, K (Chang, Kai)

Source: CHINESE PHYSICS LETTERS Volume: 37 Issue: 11 Article Number: 117102 DOI: 10.1088/0256-307X/37/11/117102 Published: NOV 2020

Abstract: We study theoretically the exciton Bose-Einstein condensation and exciton vortices in a two-dimensional (2D) perovskite (PEA)(2)PbI4 monolayer. Combining the first-principles calculations and the Keldysh model, the exciton binding energy of in a (PEA)(2)PbI4 monolayer can approach hundreds of meV, which make it possible to observe the excitonic effect at room temperature. Due to the large exciton binding energy, and hence the high density of excitons, we find that the critical temperature of the exciton condensation could approach the liquid nitrogen regime. In the presence of perpendicular electric fields, the dipole-dipole interaction between excitons is found to drive the condensed excitons confined in (PEA)(2)PbI4 monolayer flakes into patterned vortices, as the evolution time of vortex patterns is comparable to the exciton lifetime.

Accession Number: WOS:000590708300001

ISSN: 0256-307X

eISSN: 1741-3540

Full Text: https://iopscience.iop.org/article/10.1088/0256-307X/37/11/117102