Transition from etch-back to growth conditions during ammonothermal growth of GaN – a transient numerical model for convective flow and temperature distribution in a retrograde solubility configuration - Schimmel, Saskia; Tomida, Daisuke; Ishiguro, Tohru; Honda, Yoshio; Chichibu, Shigefusa F.; Amano, Hiroshi (GaN Marathon, 2024)