Two‐dimensional (2D) transition metal dichalcogenides (TMDCs) such as MoS2exhibit exceptionally strong nonlinear optical responses, while nanoscale control of the amplitude, polar orientation, and phase of the nonlinear light in TMDCs remains challenging. In this work, by interfacing monolayer MoS2with epitaxial PbZr0.2Ti0.8O3(PZT) thin films and free‐standing PZT membranes, the amplitude and polarization of the second harmonic generation (SHG) signal are modulated via ferroelectric domain patterning, which demonstrates that PZT membranes can lead to in‐operando programming of nonlinear light polarization. The interfacial coupling of the MoS2polar axis with either the out‐of‐plane polar domains of PZT or the in‐plane polarization of domain walls tailors the SHG light polarization into different patterns with distinct symmetries, which are modeled via nonlinear electromagnetic theory. This study provides a new material platform that enables reconfigurable design of light polarization at the nanoscale, paving the path for developing novel optical information processing, smart light modulators, and integrated photonic circuits.
Ferroelectric nanotubes offer intriguing opportunities for stabilizing exotic polarization domains and achieving new or enhanced functionalities by tailoring the complex interplay among the geometry, surface effects, crystal symmetry, and more. Here, phase‐field simulations to predict the room‐temperature equilibrium polarization domain structure in (001)pcPbZr0.52Ti0.48O3(PZT) nanotubes are used (pseudocubic (pc)). The simulations incorporate the influence of surface‐tension‐induced strains, which have been ignored in existing computational studies. It is found that (001)pcPZT nanotubes can host a unique class of topological polarization domain structures comprising non‐planar flux‐closures and anti‐flux‐closures that are inaccessible with ferroelectrics of planar geometry (e.g., thin‐films, nanodots). It is shown that surface‐tension‐induced strain is significantly enhanced in thin‐walled nanotubes and thereby can lead to noticeable modulation of the flux closures. Domain stability map as a function of the nanotube wall thickness and height is established. The results provide a basis for geometrical engineering of domain structures and associated functional (e.g., piezoelectric, electrocaloric) responses in ferroelectric nanotubes.
more » « less- Award ID(s):
- 2006028
- NSF-PAR ID:
- 10395262
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- Volume:
- 8
- Issue:
- 6
- ISSN:
- 2199-160X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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