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Title: Light-induced Kondo-like exciton-spin interaction in neodymium(II) doped hybrid perovskite
Abstract Tuning the properties of a pair of entangled electron and hole in a light-induced exciton is a fundamentally intriguing inquiry for quantum science. Here, using semiconducting hybrid perovskite as an exploratory platform, we discover that Nd2+-doped CH3NH3PbI3(MAPbI3) perovskite exhibits a Kondo-like exciton-spin interaction under cryogenic and photoexcitation conditions. The feedback to such interaction between excitons in perovskite and the localized spins in Nd2+is observed as notably prolonged carrier lifetimes measured by time-resolved photoluminescence, ~10 times to that of pristine MAPbI3without Nd2+dopant. From a mechanistic standpoint, such extended charge separation states are the consequence of the trap state enabled by the antiferromagnetic exchange interaction between the light-induced exciton and the localized 4 fspins of the Nd2+in the proximity. Importantly, this Kondo-like exciton-spin interaction can be modulated by either increasing Nd2+doping concentration that enhances the coupling between the exciton and Nd2+4 fspins as evidenced by elongated carrier lifetime, or by using an external magnetic field that can nullify the spin-dependent exchange interaction therein due to the unified orientations of Nd2+spin angular momentum, thereby leading to exciton recombination at the dynamics comparable to pristine MAPbI3.  more » « less
Award ID(s):
1806152
PAR ID:
10569747
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature Portfolio
Date Published:
Journal Name:
Nature Communications
Volume:
15
Issue:
1
ISSN:
2041-1723
Page Range / eLocation ID:
6084
Subject(s) / Keyword(s):
Kondo effect, spin, entanglement, light induced, excitons, semiconductor, hybrid perovskite, rare-earth, 4f spin, magnetic dopants, quantum computing, quantum coherence,
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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