Modulation of the second-order nonlinear tensor components in multiple-quantum-well structures

In this paper, we present experimental results which demonstrate that quantum-well intermixing techniques can be used to modulate the magnitude of the second-order nonlinear coefficient χ⁽²⁾. Impurity-free vacancy disordering with SiO₂ and Ga₂O₃ caps was used to modulate the position of the band edge and hence, the magnitude of χ_eff⁽²⁾ . Using a coupled quantum-well structure we were able to demonstrate modulation of the d₃₃ tensor components associated with the asymmetric structure and of the d₁₄ component associated with the bulk crystal structure