Fig. 4: Effect of synthesis conditions on products.
From: Autonomous reinforcement learning agent for chemical vapor deposition synthesis of quantum materials
a A generated synthesis profile starting from low temperature and low gas concentrations. The RL model quickly ramps up the temperature up to 7 ns to promote reduction and sulfidation and then lowers the temperature to intermediate values to promote crystallization. This profile generates significant phase fraction of 2H starting from 10 ns. b A generated synthesis profile starting from high temperature and high S2 concentrations. The RL-NADE model retains the high temperature at early stages of synthesis and slowly anneals the system to intermediate temperatures after 10 ns. This schedule promotes relatively late crystallization and 2H phase formation. c Synthesis profiles with initially low S2 concentrations yield significantly higher phase fraction of 2H in the final product compared to profiles containing higher S2 concentrations at t = 0 ns. d, e Synthesis schedules are relatively insensitive to the initial concentration of reducing species, H2S and H2.
