(color online) (a) Schematic of the graphene SA mode-locked VECSEL setup (left). Linear absorption and field intensity enhancement at the single-layer graphene location corresponding to the DBRs without SiO₂ (), a λ/12 layer of SiO₂ (), a λ/8 layer (), and a λ/4 layer () (right-top). Mode-locking results showing the autocorrelation trace, corresponding to a pulse duration of 466 fs, and the optical spectrum (right-bottom).^[46] (b) The schematic of the V-cavity with the gain chip at the fold and the graphene SA mirror and outcoupler at either end (left). The optical spectrum of the VECSEL cavity operating at 9.3 W, with a spectral bandwidth of 6.92 nm (middle) and the corresponding autocorrelation trace (right).^[47]