Experimental studies on magnetization in the excited state by using the magnetic field effect of light scattering based on multi-layer graphene particles suspended in organic solvents.
This article reports on experimental studies on magnetic polarization in the excited state by using magnetic field effects of light scattering (MFELS) together with a photoexcitation beam based on fluorinated multi-layer graphene (FG) particles suspended in an organic solvent. We observe that a magnetic field can change the light scattering of a 532 nm laser beam from the suspended FG particles, generating a MFELSsignal with an amplitude of 60% at 900 mT. This phenomenon indicates that the suspended FG particles experience a magnetization force, leading to an orientation of the suspended FG particles in a magnetic field. We find that the magnetization force is a function of a solvent dielectric constant, an analogue phenomenon similar to magneto-electric coupling. More importantly, in the excited state the suspended FG particles exhibit more pronounced MFELS, as compared with the ground state, when the magnetic field effects of light scattering are combined with a photoexcitation beam of 325 nm. Clearly, the FG particles in the excited state possess a stronger magnetization relative to the ground state. This excitation-enhanced magnetization suggests an interaction between the magnetization from the localized spins and the polarization from delocalized π electrons in the FG particles. Therefore, the magnetic field effects of light scattering provide a convenient experimental method to investigate the magnetization of nanoparticles in the excited state.
Department of Materials Science and Engineering, University of Tennessee-Knoxville, Tennessee 37996, USA. bhu@utk.edu.
Lei
L
He
Department of Materials Science and Engineering, University of Tennessee-Knoxville, Tennessee 37996, USA. bhu@utk.edu.
Mingxing
M
Li
Department of Materials Science and Engineering, University of Tennessee-Knoxville, Tennessee 37996, USA. bhu@utk.edu.
Hengxing
H
Xu
College of Science, Beijing Jiaotong University, Beijing 100044, China and Department of Materials Science and Engineering, University of Tennessee-Knoxville, Tennessee 37996, USA. bhu@utk.edu.
Bin
http://orcid.org/0000-0002-1573-7625
B
Hu