Second Harmonic Generation in Imperfect Crystals

Second harmonic generation (SHG) materials allow optical frequency doubling that is crucial to advanced optical and photonic applications in telecommunications, lasers, etc.. The second order polarizability required for a material to be SHG active depends on a lack of centrosymmetry but generally benefits from even lower symmetry. In this talk, we highlight how non-ideal features of real materials change the local symmetry and modulate their SHG response. The effects are examined using the momentum space distribution of contributions to the total SHG response for non-ideal features, focusing on stacking faults and dopants. Lastly, we describe a high-fidelity approach for treating the effects of chemical disorder in solid solutions and compare its performance to various approximations.