4 papers
Many-mode grating couplers by avoiding undesired couplings
Nazar Pyvovar, Hao Li, Zhaowei Dai +1
To couple many independent modes from free space to on chip, the key challenge is not enhancing the many necessary coupling rates (scattering-matrix elements) between targeted mode…
Multimode grating couplers via foundry-compliant inverse design
Hao Li, Nazar Pyvovar, Zhaowei Dai +1
We apply a systematic inverse design approach to discover foundry-compliant, multilayer grating couplers that can efficiently couple a number of independent waves from free space t…
Exploring the equivalence of causality-based and quantum mechanics-based sum rules for harmonic generation in nonlinear optical materials
Theodoros T. Koutserimpas, Hao Li, Owen D. Miller +1
The Kramers-Kronig relations and various oscillator strength sum rules represent strong constraints on the physical response of materials. In this work, taking inspiration from the…
Approaching upper bounds to resonant nonlinear optical susceptibilities with inverse-designed quantum wells
Hao Li, Theodoros T. Koutserimpas, Francesco Monticone +1
We develop a unified framework for identifying bounds to maximum resonant nonlinear optical susceptibilities, and for "inverse designing" quantum-well structures that can approach…