It is crucial to identify an efficient system for the sensing of formaldehyde (FD). The feasibility of utilising a B
3
S monolayer (B
3
SML) detector of FD was evaluated by analysing the adsorption, ...optical properties, gas-sensing behaviour, and electronic properties of FD and other gas molecules on the B
3
SML under density functional theory (DFT). The pristine B
3
SML was found to have satisfactory sensing toward FD molecules. The analysis of the adsorption mechanisms, geometric systems, adsorption energy, electronic and optical properties, charge transfer, and electron density differences revealed that the B
3
SML could potentially serve as an FD detector. It can be said that the B
3
SML is a promising sensor for detecting FD molecules. The present study contributes to the existing knowledge of gas-surface interactions and helps develop 2D sensor structures to detect FD gas molecules.
Fiber optic interferometers have been studied extensively for sensing various physical characteristics such as temperature, strain, pressure, and refractive index. Fabry-Perot, Mach-Zehnder, ...Michelson, and Sagnac are the four different types. In this case, in this study, the operational principles of Mach-Zehnder interferometric sensor are examined. fabrication techniques, as well as application sectors. The technologies of interferometric sensors are described in detail to demonstrate their great potential in practical uses. Mach-Zehnder The interferometer is a device that measures the difference in phase shifts Between two coherent collimated beams. According to this fundamental Principle, various devices can be designed. Several devices, including various types of in-line MZI optical sensors, all-optical switches and modulator, can be created using this basic principle are discussed in this paper.