Field‐Switchable Broadband Polarizer Based on Reconfigurable Nanowire Assemblies

Abstract

This article is protected by copyright. All rights reserved. 2Reconfigurability is one of the most critical properties of nanophotonic systems and, consequently, methods for enabling a significant degree of functionality are highly sought after.However, dynamically responsive control in top-down fabricated photonic structures often requires extreme conditions and yields moderate modulation capability. In sharp contrast to top-down methods, directed self-assembly of micro-and nanoparticles offers a distinct avenue for reconfigurable photonics. In the present work, gold nanowire lattices are formed via electric field directed assembly in order to take advantage of their collective optical properties. The lattices are reconfigured on-demand between two different functional states, in the form of broadband polarizers. By selectively switching the electric field between two orthogonal electrode pairs, a maximum transmission contrast of ca. 50% is observed in the near-infrared regime. Moreover, the reconfigurable transmission spectra, which are highly dependent on the nanowire size and electric field conditions, are reversible. The demonstrated proof-of-concept nanowire lattice polarizer provides potential for electrically reconfigurable photonic devices such as ultra-compact polarization components, electro-optic switches, and on-chip modulators. electric field directed assembly of gold nanowires to form reconfigurable 2D lattices and present a tunable broadband polarizer in a proof-of-concept demonstration.

Autonomous Formation and Annealing of Colloidal Crystals Induced by Light‐Powered Oscillations of Active Particles

“…As shown in studies by Bevan, there is still much to learn about crystallization dynamics, defect migration, and grain boundary fluctuations in assembled materials at the microscale, which can act as models for molecular crystal lattices . As for the design of new materials, the reversible assembly of various types of passive particles has applications in many areas: reconfigurable structural color, polarization, or wiring devices, structures with chirality or shape‐memory, and even antireflective coatings, photonic crystals, and plasmonic materials with adaptive properties …”

“…Thus, the “autonomous annealing” behavior described here could be applied to designing systems of “self‐switching” structural colors. Similarly, reconfigurable polarizers could also benefit from this behavior, among other adaptive materials …”

“…As shown in studies by Bevan, there is still much to learn about crystallization dynamics, defect migration, and grain boundary fluctuations in assembled materials at the microscale, which can act as models for molecular crystal lattices. [21,22] As for the design of new materials, the reversible assembly of various types of passive particles has applications in many areas: reconfigurable structural color, polarization, or wiring devices, [23][24][25][26] structures with chirality or shape-memory, [27] and even antireflective coatings, photonic crystals, and plasmonic materials with adaptive properties. [28][29][30][31][32] While most previous studies have focused on the selfassembly of active particles into dynamic clusters or the selfassembly of passive particles using external fields, we present here a system that demonstrates the reversible autonomous assembly and defect annealing of colloidal crystals containing primarily passive particles.…”

“…Similarly, reconfigurable polarizers could also benefit from this behavior, among other adaptive materials. [25]…”

Size‐ and Interface‐Modulated Metal–Insulator Transition in Solution‐Synthesized Nanoscale VO2‐TiO2‐VO2 Heterostructures

“…In summary,wehave demonstrated the synthesis of VO 2 -TiO 2 -VO 2 nanorod heterostructures with tunable VO 2 domain sizes and TiO 2 -VO 2 interfacial characteristics.B y using faceted TiO 2 nanorods as seeds,the switchable M1 form of VO 2 could be epitaxially grown from solution, yielding several distinct classes of nanoscale heterostructures that exhibit well-defined insulator-to-metal transitions.The ability to incorporate VO 2 (M1) into such hybrid particles opens the door to future studies of size-and interface-dependent behavior at small length scales,aswell as possible integration into assembled device architectures. [10,11,33] Figure 5. TEM, STEM-EDS, HRTEM, SAED, and corresponding FFT data for a)-e) Type Dand f)-j) Type BVO 2 -TiO 2 -VO 2 nanorod heterostructures.…”