Research On Coupling Mechanism Of Left - Handed Materials And Quantum Wells

Artificial materials with simultaneously negative permittivity and permeability,namely, left-handed materials (LHM), are currently one of the most scientifically interesting topics because of their unusual properties to those conventional electromagnetic media, such as negative refraction and sub-diffraction-limited imaging by planar slab.In2001, using metal wire arrays and metal ring resonator structure, Smith et al. confirmed the performance of the left-handed materials in the microwave band for the first time. Thereafter, For achieving a left-hand performance from the microwave band to the infrared and even visible band, a large number of new structure based on splitting ring deformation was proposed, for example:S-shaped structure, the omega-shaped structure, H-shaped structure, etc.. Double fishnet structure is distributed in the metal-dielectric-metal sandwich structure hole array of left-handed materials, this structure take advantage for negative permittivity, negative permeability and excellent electromagnetic mode. In addition, it is manufactured easily and potential in optoelectronic devices. The composite system combining double fishnet structure wih low-dimensional semiconductor structures can adjust negative refraction.This thesis, the metal-dielectric-metal microcavity, the metal layer of the micro-cavity are carved with the periodic subwavelength rectangular hole arrays, and the dielectric layer in the middle is the GaAs quantum well, is proposed. The optical mode,coupling mechanism between the optical mode and the QW subband transitions and the electric field distribution in this microcavity are studied theoretically. It is found that the double-fishnet negative refractive properties can be tunnble by coupling microcavity optical modes and QW Intersubband Transition.(1) There are three optical eigenmodes in metal-GaAs QW-metal microcavity. two eigenmodes in microcavity, Gap Surface Plasmon (GSP), Localized Surface Plasmon (LSP) and QW Intersubband Transition (ISBT). Especially, GSP coupled with ISBT effectively, while it is weak between LSP and ISBT. (2) QW is one of classical low-dimensional semiconductor materials, and it plays an important role in device applications. With the developing of material growth technology, the controllability of the QW become ease. Coupling mechanism between the microcavity electromagnetic modes and QW Intersubband Transition (ISBT) can be discussed in detail by changing the characteristics of the QW parameter values.(3) The coupling between optical microcavity mode and QW subband transition can be adjusted by adding a biased voltage into the DF structure, that it is, adjusting the concentration of the electron in the quantum well. At the same time, the situ adjustment of negative refraction can be achieved. This work has a great advantage in optoelectronic devices.(4) According to the study on coupling between the anisotropic semiconductor material (like QW)and DF microcavity, it was found that DF microcavity eigenmodes in different directions of the electric field coupler can be combined with the alignment direction of the respective anisotropic medium.These studies show the characteristics of the metamaterial (DF) structure and low-dimensional semiconductor QW optical metamaterials. It may pave a promising way for tunable optical applications of NRI materials, and for studying on slow-wave, compensating for the loss, adding the gain medium in structures.