2D ferroelectrics for nonlinear flat optics
Abstract
Second-order nonlinear coefficients (2) underlie many important effects including various forms of frequency conversions and electro-optic (EO) effects that enable phase or amplitude modulations of electromagnetic waves. Rather high nonlinear efficiencies are currently available in crystals such as LiNbO3. However, due to a limited conversion efficiency, existing frequency converters or EO modulators based on those conventional nonlinear crystals are long (greater than 5mm), require large voltages (greater than100V), or difficult to integrate on standard semiconductor materials. In this DEPSCoR project, exceptionally large (2) recently uncovered in two-dimensional (2D) ferroelectrics will be leveraged to study new means of electromagnetic signal generation and conversion. Specifically, we will focus on a 100 GHz to 1 THz frequency range where coherent light sources or modulators are scarcely available. To this end, we target a few distinct physical processes in 2D ferroelectrics, which are promising but thus far lacked systematic study- 1) Pockels effects in 2D ferroelectrics; 2) Parametric down conversion in 2D ferroelectrics; and 3) Sub-THz ferroelectric domain dynamics. Furthermore, we will pursue engineering approaches such as sub-wavelength patterning of 2D ferroelectrics, that could further enhance the nonlinear processes by either a resonant enhancement of electric and magnetic dipole moments in driving fields or by concepts analogous to a quasi-phase matching. Our team will tackle these topics by a joint experiment and theory collaboration. First-principles theoretical modeling will be utilized to quantitively evaluate the nonlinear and Pockel coefficients and to guide efficient experimental studies. Atomically thin 2D ferroelectrics are ultimate building blocks for future development of flat optics or on-chip applications. The outcome we expect is to pave the way towards realizing efficient frequency conversion and photon modulation at much smaller footprints than available in current devices, by studying fundamental nonlinear optical effects in 2D ferroelectrics.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 06, 2024
- Source ID
- FA95502310500
Entities
People
- Hiroyuki Nakamura
Organizations
- Air Force Office of Scientific Research
- Office of the Secretary of Defense
- University of Arkansas System