Studies on semiconductor-based long-period fiber grating structure to realize memory application: an alternate of CD, DVD, and B-ray storage devices

The present research paper provides information to design fiber-based Bragg’s grating structure to absorb and transmit the signals of 405 nm, 650 nm, and 780 nm wavelengths only. The reason for choosing such wavelengths is that the wavelength 405 nm is used for writing and reading the CD, while the wavelength 650 nm is used for writing and reading the DVD and the wavelength 780 nm is used for writing and reading the blue ray. The theory of mechanisms deals with the reflection, absorption, and transmission which is estimated through numerical investigation. The detailed analysis of efficiencies of both input source (GaAs-based light-emitting diode) as well as fiber-based Braggs grating is made through the plane wave expansion method. As far as the result is concerned, the efficiency of LED is about 100% corresponding to the all. Further, the silicon-based fiber grating structure absorbs 100% of the signals absorbed by the grating structure and, subsequently, these wavelengths (405 nm, 650 nm, and 780 nm) are transmitted by the structure after the incident of 1550 nm to it. Finally, it is also realized that the different proposed structures permit different wavelengths. For example, the longer grating structure permits longer wavelength, whereas the shorter structure allows short wavelength. Lastly, a mathematical model is developed which provides the relationship between the thickness of Braggs grating and allowed wavelengths. Finally, error analysis is analyzed through numerical model.