Generating and processing optical waveforms using spectral singularities

We show that a laser at threshold can be utilized to generate the class of coherent and transform-limited waveforms (vt-z)mei(kz-ωt) at optical frequencies. We derive these properties analytically and demonstrate them in semiclassical time-domain laser simulations. We then utilize these waveforms to expand other waveforms with high modulation frequencies and demonstrate theoretically the feasibility of complex-frequency coherent absorption at optical frequencies, with efficient energy transduction and cavity loading. This approach has potential applications in quantum computing, photonic circuits, and biomedicine.