The turn-on dynamics and energy efficiency of control over low-voltage AlGaAs/GaAs/InGaAs lasers-thyristors emitting at a wavelength of 905 nm have been experimentally studied in various control modes: (i) optical activation of the p-GaAs base with external light at a wavelength of 1068 nm and (ii) standard mode of control with pulsed current. It was shown that the turn-on of low-voltage lasers-thyristors by long-wavelength light with photon energy lower than the energy gap width of the p-GaAs base occurs via activation of deep levels. It was demonstrated that, for low-voltage lasers-thyristors with maximum blocking voltage of up to 12 V, the turn-on delay times under optical and electrical activation fall in the range 50-1200 ns. Under optical control by external source at a wavelength of 1068 nm, amplitude of optical power introduced into the p-GaAs base reached a value of 300 mW, and the energy absorbed in the p-GaAs base during the control pulse was 30-40 fJ. In the case of the electrical control, the control current density was as high as 20 A cm −2 , and the energy absorbed in the p-GaAs base during the control pulse was 43-47 pJ.