Control of the temporal profile of the local electromagnetic field near metallic nanostructures

We study control of the temporal profile of the local electric field in the vicinity of a small doped semiconductor or metal nanostructure. Unlike in the case of control in a gas or liquid phase, the collective response of electrons in the nanostructure may significantly enhance different frequency components of the external field. This enhancement strongly depends on the geometry of the nanostructure and can substantially modify the temporal profile of the local field. The changes in the amplitude and phase of the local field are studied using linear response theory within the random phase approximation. The inverse problem of finding the external electromagnetic field to generate an arbitrary target temporal profile of the local field, including the time-dependent polarization of the field, is considered and solved. We systematically study the pulse enhancement and shape distortion effects for a set of control pulses of various shapes.