Controlled spontaneous emission in a semi-infinite rectangular waveguide
摘要
The main focus of this paper is on investigating the spontaneous emission process of an excited two-level atom interacting with a vacuum in a rectangular waveguide surrounded by a perfect electric conductor. According to the second quantization formalism, the location and direction of the electric dipole are the main factors governing the process of suppression or enhancement. The stationary approach assumes that the electric dipole has a fixed direction; hence, spontaneous emission is presented in three perpendicular Cartesian coordinates. This approach can be considered valid when certain conditions are available, such as a short waveguide length and high atomic velocity. It explicitly ignores the fact that the electric dipole vector is a dynamic variable. On the other hand, the dynamic approach presents the total spontaneous emission as a directional sum of possible coordinates, which improves the product and makes it closer to experimental results. This approach only requires pre-excitation by an external light mode in order to control the expected directions. The single-mode waveguide offers a radical solution that completely avoids the electric dipole orientation obstacle. Its production has been made possible by advances in micro-fabrication technology.