Superoscillations Made Super Simple

Abstract: In ordinary circumstances the highest frequency present in a wave is the highest frequency in its Fourier decomposition. It is however possible for there to be a spatial or temporal region of the wave which locally oscillates at a still greater frequency, in a phenomenon known as superoscillation. Superoscillations find application in wide range of disciplines, but at present their generation is based upon constructive approaches which are difficult to implement. Here we address this, exploiting the fact that superoscillations are a product of destructive interference to produce a prescription for generating superoscillations from the superposition of arbitrary waveforms. As a first test of the technique, we use it to combine four THz laser fields generated by periodically poled Lithium Niobate. From this, we are able to predict and observe for the first time THz optical superoscillations in the temporal domain. The ability to generate superoscillations in this manner has potential application in a wide range of fields. It may for example contribute to the experimental realization of the complex pulses required by quantum control, and the generation of attosecond pulses without resorting to nonlinear processes.