Optical properties of quantum dot and electron-quantum dot  behaviors in on heat and laser field

Quantum dots (QDs) are widely studied for their unique optical and electronic properties. Research has shown that external factors like lasers and magnetic fields influence their optical behavior. Laser-assisted scattering, especially with Gaussian potentials, affects QD dynamics. While studies have examined QD interactions under linearly polarized laser fields, there is limited research on circularly polarized fields and their effect on differential cross-sections (DCS). Moreover, combined studies of electron-QD scattering with laser and thermal effects alongside optical properties remain lacking. The objective of this work is to study the optical properties of QDs and their behavior in laser and thermal environments in the presence of electrons. Two approaches were employed: theoretical and experimental. Theoretically, thermal wave functions were developed for QDs in a laser field with three polarization cases using a Gaussian potential. The DCS was analyzed using the S-matrix, Bessel functions, and the Kroll-Watson approximation, revealing that DCS increases with temperature in electron–QD interactions. Experimentally, QDs of varying concentrations (100%, 50%, 25%, 12.5% v/v) were synthesized using a citric acid and thiourea mixture (2:1 ratio) and heated for 2 minutes at 200–250°C in a 1100 W microwave. Optical properties were measured using a rotating spectrometer and a Theremino spectrometer under different conditions: laser exposure (1–4 minutes), temperatures (30–60°C), and magnetic fields (0.5–1.5 k Gauss). Results showed that laser, temperature, and magnetic field significantly and nonlinearly affect QD transmittance and refractive index. The total molecular cross-section (TMCS) also increased with temperature. Comparison of experimental TMCS and theoretical DCS at low energy showed similar trends, though TMCS values were consistently higher.