Magneto-Optics of Excitons Interacting with Magnetic Ions in CdSe/CdMnS Colloidal Nanoplatelets

Elena V Shornikova; Dmitri R Yakovlev; Danil O Tolmachev; Vitalii Yu Ivanov; Ina V Kalitukha; Victor F Sapega; Dennis Kudlacik; Yuri G Kusrayev; Aleksandr A Golovatenko; Sushant Shendre; Savas Delikanli; Hilmi Volkan Demir; Manfred Bayer

doi:10.1021/acsnano.0c04048

Magneto-Optics of Excitons Interacting with Magnetic Ions in CdSe/CdMnS Colloidal Nanoplatelets

ACS Nano. 2020 Jul 28;14(7):9032-9041. doi: 10.1021/acsnano.0c04048. Epub 2020 Jul 2.

Authors

Elena V Shornikova¹, Dmitri R Yakovlev^{1

2}, Danil O Tolmachev^{1

2}, Vitalii Yu Ivanov³, Ina V Kalitukha², Victor F Sapega², Dennis Kudlacik¹, Yuri G Kusrayev², Aleksandr A Golovatenko², Sushant Shendre⁴, Savas Delikanli^{4

5}, Hilmi Volkan Demir^{4

5}, Manfred Bayer^{1

2}

Affiliations

¹ Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany.
² Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia.
³ Institute of Physics, Polish Academy of Sciences, PL-02-668 Warsaw, Poland.
⁴ LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University, 639798 Singapore.
⁵ Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey.

PMID: 32585089
DOI: 10.1021/acsnano.0c04048

Abstract

Excitons in diluted magnetic semiconductors represent excellent probes for studying the magnetic properties of these materials. Various magneto-optical effects, which depend sensitively on the exchange interaction of the excitons with the localized spins of the magnetic ions can be used for probing. Here, we study core/shell CdSe/(Cd,Mn)S colloidal nanoplatelets hosting diluted magnetic semiconductor layers. The inclusion of the magnetic Mn²⁺ ions is evidenced by three magneto-optical techniques using high magnetic fields up to 15 T: polarized photoluminescence, optically detected magnetic resonance, and spin-flip Raman scattering. We show that the holes in the excitons play the dominant role in exchange interaction with magnetic ions. We suggest and test an approach for evaluation of the Mn²⁺ concentration based on the spin-lattice relaxation dynamics of the Mn²⁺ spin system.

Keywords: CdSe nanoplatelet; colloidal nanocrystals; diluted magnetic semiconductors; magneto-optics; optically detected magnetic resonance; spin-flip Raman scattering.