[Junghyun Kim and Prof. Je-Geun Park] Rapid suppression of quantum many-body magnetic exciton in doped van der Waals antiferromagnet (Ni,Cd)PS3
The unique discovery of magnetic exciton in van der Waals antiferromagnet NiPS3 arises between two quantum many-body states of a Zhang-Rice singlet excited state and a Zhang-Rice triplet ground state. Simultaneously, the spectral width of photoluminescence originating from this exciton is exceedingly narrow as 0.4 meV. These extraordinary properties, including the extreme coherence of the magnetic exciton in NiPS3, beg many questions. We studied doping effects using Ni1-xCdxPS3 using two experimental techniques and theoretical studies. Our experimental results show that the magnetic exciton is drastically suppressed upon a few % Cd doping. All these happen while the width of the exciton only gradually increases, and the antiferromagnetic ground state is robust. These results highlight the lattice uniformity's hidden importance as a prerequisite for coherent magnetic exciton. Finally, an exciting scenario emerges: the broken charge transfer forbids the otherwise uniform formation of the coherent magnetic exciton in (Ni,Cd)PS3.
Junghyun Kim, Woongki Na, Jonghyeon Kim, Pyeongjae Park, Kaixuan Zhang, Inho Hwang, Young-Woo Son, Jae Hoon Kim, Hyeonsik Cheong and Je-Geun Park
Nano Lett. 2023, 23, 10189-10195
Nano Lett. 2023, 23, 10189-10195