  Using the recently reported mode locking effect we demonstrate a highly
robust control of electron spin coherence in an ensemble of (In,Ga)As quantum
dots during the single spin coherence time. The spin precession in a transverse
magnetic field can be fully controlled up to 25 K by the parameters of the
exciting pulsed laser protocol such as the pulse train sequence, leading to
adjustable quantum beat bursts in Faraday rotation. Flipping of the electron
spin precession phase was demonstrated by inverting the polarization within a
pulse doublet sequence.
