Light-induced paramagnetism in colloidal Ag+-doped CdSe nanoplatelets

• Main Authors: Najafi, Arman, Sharma, Manoj, Delikanli, Savas, Bhattacharya, Arinjoy, Murphy, Joseph R., Pientka, James, Sharma, Ashma, Quinn, Alexander P., Erdem, Onur, Kattel, Subash, Kelestemur, Yusuf, Kovalenko, Maksym V., Rice, William D., Demir, Hilmi Volkan, Petrou, Athos
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2021
• Subjects: Engineering::Materials; CdSe Nanoplatelets; Light-induced Magnetism
• Online Access: https://hdl.handle.net/10356/147028
• Institution: Nanyang Technological University

We describe a study of the magneto-optical properties of Ag+-doped CdSe colloidal nanoplatelets (NPLs) that were grown using a novel doping technique. In this work, we used magnetic circularly polarized luminescence and magnetic circular dichroism spectroscopy to study light-induced magnetism for the first time in 2D solution-processed structures doped with nominally nonmagnetic Ag+ impurities. The excitonic circular polarization (PX) and the exciton Zeeman splitting (ΔEZ) were recorded as a function of the magnetic field (B) and temperature (T). Both ΔEZ and PX have a Brillouin-function-like dependence on B and T, verifying the presence of paramagnetism in Ag+-doped CdSe NPLs. The observed light-induced magnetism is attributed to the transformation of nonmagnetic Ag+ ions into Ag2+, which have a nonzero magnetic moment. This work points to the possibility of incorporating these nanoplatelets into spintronic devices, in which light can be used to control the spin injection.