Research Interests   My research interests focus on the investigation of low-dimensional electronic and magnetic materials, including correlated electron systems, multiferroic materials, charge density waves, transition metal oxides, and semiconductors, via optical, magneto-optical, electro-optical, and transport techniques. Complex oxides display a variety of interesting properties under different conditions, and understanding their properties is essential for potential device applications. For instance, multiferroic materials demonstrate a unique magnetoelectric coupling, offering the tuning of their magnetic properties by an electric field and vice versa.   My current research projects focus on studies of doped wide band gap semiconductors, multiferroics (including LuFe2O4 and RMnO3 family), and spinel ferrites family (NiFe2O4, CoFe2O4, and ZnFe2O4). I am particularly interested in the growth and investigation of thin films of these materials using different experimental methods, including optical spectroscopy, magneto-optical measurements, resistivity, and dielectric measurements. Thin films of these materials will be prepared on suitable single-crystal substrates using RF sputtering deposition. The film samples will then be investigated for their structures, optical/electronic properties, and spin-charge-lattice coupling. For example, the spectroscopic studies will help reveal the underlying structural characteristics, electronic structures, the phase transitions, and other physical properties of the materials. We can perform the optical studies using the spectrophotometer (190-3300 nm wavelength range) equipped with a variable temperature cryostat (4 - 500 K) in both reflectance and transmittance modes.   It is well known that electronic excitations within the transition metal d manifolds of complex oxides are sensitive to the local crystal field environment, for example octahedral or tetrahedral crystal fields. Moreover, the electronic excitations can also be sensitive to magnetic order if the charge, lattice, and spin channels are coupled. And such a coupling process in the structure strongly influences the physical properties of materials. For example, multiferroic oxides, such as Ni3V2O8, HoMnO3, and BiFeO3, display a significant charge-spin-lattice coupling, leading to their interesting physical properties. Therefore, it is ideal to use an optical probe, such as the UV-VIS-NIR spectrophotometer, to investigate transition metal d to d on-site excitations and spin-charge-lattice coupling effects in order to understand the structure and physical properties of materials.   Some highlights of our past projects: Multiferroic LuFe2O4 Thin Films Spinel Ferrites CoFe2O4 and NiFe2O4 Thin Films Multiferroic Hexagonal HoMnO3 Zinc Oxide Thin Films   Top