Photonic Crystal And Negative Refraction Effects Based On Magnetic Fluids

This paper mainly studies the following two aspects content:(1) Tunable one-dimensional photonic crystals band gap based on magneticfluids. The study tunable principle of the band gap. Pave the way for the study tunablenegative refraction of two-dimensional photonic crystal.(2) Tunable negative refraction of two-dimensional photonic crystals made ofsilicon cylinders hexagonally arranged in MnFe2O4magnetic liquids was studied. Theplane wave expansion and finite-difference time-domain (FDTD) methods were usedto calculate and simulate their band structures, equi-frequency surfaces (EFS) andnegative refraction properties. For the TE mode, the negative refraction of thetwo-dimensional photonic crystal made of the silicon column-magnetic liquid systemcan be tuned by the magnetic field. When the volume fraction of magneticnanoparticles within the magnetic liquids and the frequency of the incident light arefixed, the deflection angle of the refraction light and the absolute value of the negativerefractive indices will increase with the external magnetic field gradually. When thevolume fraction of magnetic nanoparticles within magnetic liquids and the strength ofthe external magnetic fields are fixed, the absolute value of the negative refractiveangle and negative refractive indices will decrease with the normalized frequency ofthe incident light. In addition, when the external magnetic fields and the normalizedfrequency of the incident light are fixed, the negative refraction will weaken with theincrease of magnetic nanoparticle volume fraction of background solution.These researches have benefits for us to futher understanding the novel photonicdevices, and can offer theoretical direction for the manufacture of the novel opticalcomponents based on the magnetic fluid.