Proposal for fast optical spin rotations in quantum dots

A proposal for fast optical rotation of the spin of an electron in a quantum dot is presented. Hyperbolic secant pulses of appropriate polarization are employed to induce a relative phase between two spin basis states. This phase is the angle of spin rotation, and the polarization determines the direction of the spin. Varying both allows for the construction of arbitrary rotations. Simulations with typical parameters for InAs self-assembled quantum dots—including dissipative dynamics—show that the fidelity of the operations is at least 99%. The effect of deviation from the ideal pulse shape is also examined.