“…Smoothened QW boundaries induce larger band gap and resultant blue shift of PL peaks. There are several techniques for QWI, such as impurity-induced disordering (IID) [12], impurity-free vacancy disordering (IFVD) [13,14], ion irradiationinduced disordering [15,16], plasma damage-induced intermixing [17,18], and laser-induced disordering [19]. Most of QWIs, except the ion irradiation-induced disordering, are atom diffusion-based technologies and they are hardly applicable for LD structures with a thick cladding layer (>1 mm) [20,21].…”