  We consider a nanostructure consisting of a semiconductor quantum dot coupled
to a metal nanoparticle, and show with numerical simulations that the exciton
state of the quantum dot can be robustly generated from the ground state even
for small interparticle distances, using conventional chirped pulses with
Gaussian and hyperbolic secant envelopes. The asymmetry observed in the final
exciton population with respect to the chirp sign of the applied pulses is
explained using the nonlinear density matrix equations describing the system,
and is attributed to the real part of the parameter emerging from the
interaction between excitons in the quantum dot and plasmons in the metal
nanoparticle. The simplicity of the conventional chirped pulses, which can also
be easily implemented in the laboratory, make the proposed robust quantum
control scheme potentially useful for the implementation of ultrafast
nanoswitches and quantum information processing tasks with semiconductor
quantum dots.
