Design of efficient modally phase-matched SHG waveguides with automatic differentiation

Ryan Hamerly; Alexander Sludds; Saumil Bandyopadhyay; David Heydari; Mircea Catuneanu; Dirk R. Englund; Kambiz Jamshidi

doi:10.1117/12.2624485

24 May 2022 Design of efficient modally phase-matched SHG waveguides with automatic differentiation

Ryan Hamerly, Alexander Sludds, Saumil Bandyopadhyay, David Heydari, Mircea Catuneanu, Dirk R. Englund, Kambiz Jamshidi

Proceedings Volume PC12130, Metamaterials XIII; PC1213002 (2022) https://doi.org/10.1117/12.2624485
Event: SPIE Photonics Europe, 2022, Strasbourg, France

Abstract

Subwavelength grating (SWG) metamaterial structures are excellent platforms for guided-wave nonlinear optics, but their design and optimization are challenging due to the large number of geometric degrees of freedom and the need for compute-intensive 3D simulations. Here, we demonstrate inverse design of χ(2) SWG waveguides using an efficient and accurate differentiable plane-wave expansion (PWE) eigensolver. Our solver, which incorporates sparse iterative algorithms and subpixel smoothing, enables efficient eigensolution and end-to-end differentiation from geometric parameters to the SWG figure of merit, which depends both on the eigenvalues (first-order perturbation theory) and the eigenvectors and group indices (second-order perturbation theory), both in forward- and reverse-mode. We apply this solver to the design and optimization of metamaterial waveguides for two types of backward SHG: idler-reversed and pump-reversed. This approach may find use in designing periodic structures more generally, including nanobeam cavities, slow-light modulators, and vertically coupled resonators.

Conference Presentation

Citation Download Citation

Ryan Hamerly, Alexander Sludds, Saumil Bandyopadhyay, David Heydari, Mircea Catuneanu, Dirk R. Englund, and Kambiz Jamshidi "Design of efficient modally phase-matched SHG waveguides with automatic differentiation", Proc. SPIE PC12130, Metamaterials XIII, PC1213002 (24 May 2022); https://doi.org/10.1117/12.2624485

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available