Theoretical investigation of the photocycle dynamics of the Archaerhodopsin 3 based fluorescent voltage sensor Archon2

•Photocycle dynamics of fluorescent voltage sensor Archon2 simulated numerically.•Photocycle schemes and reaction coordinate diagrams are developed.•Photoinduced changeover of of dark-adapted Archon2 to light-adapted Archon2.•Quantum yields of forward and backward photoisomerization of Archon2 are determined.•Time constants of deprotonation, re-protonation, dark recovery and ground-state isomerization.