  We consider the Gerdjikov-Ivanov equation in the quarter plane with Dirichlet
boundary data and Neumann value converging to single exponentials $\alpha {\rm
e}^{{\rm i}\omega t}$ and $c{\rm e}^{{\rm i}\omega t}$ as $t\to\infty$,
respectively. Under the assumption that the initial data decay as $x\to\infty$,
we derive necessary conditions on the parameters $\alpha$, $\omega$, $c$ for
the existence of a solution of the corresponding initial boundary value
problem.
