Enhanced polarization sensitivity and tunability in truncated pyramidal GaAs quantum dots for FIR applications

Abstract

The far-infrared (FIR) spectrum, covering wavelengths from 20 to 1000 $\mu m$, presents significant challenges for the manipulation and detection of polarized light, especially in the short-wavelength FIR range of 20–100 $\mu m$. This study investigates the effectiveness of truncated pyramidal GaAs quantum dots in improving the absorption coefficient of polarized light within this range. Utilizing the finite difference method to obtain numerical solutions of the Schrödinger equation within the adiabatic approximation, we analyze the effects of various base shapes—equilateral hexagon, irregular hexagon, and equilateral triangle—on the optical absorption coefficients when subjected to an electric field with different directions and magnitudes. Our results reveal that triangular pyramidal quantum dots offer enhanced polarization sensitivity and greater tunability of absorption peaks compared to structures with other base shapes. Moreover, the direction of the applied electric field is crucial for tuning the absorption peaks in the desired range of FIR wavelength. These findings demonstrate the potential of truncated pyramidal GaAs quantum dots not only for improving sensing technologies but also for managing electromagnetic interference in advanced communication systems.