Superstructures of Multielement Colloidal Molecules: Efficient Pathways to Construct Reconfigurable Photonic and Phononic Crystals

Abstract

Motivated by recent advances in synthesis and characterization of complex colloidal building blocks, the self-assembly behavior and transport properties of novel superstructures of multielement colloidal molecules are explored with applications in areas such as phononics, photonics, and photovoltaics. Using an analytical/computational framework, the connectivity landscape of various shapes of colloidal molecules is examined to propose new multicomponent superstructure phases that can self-assemble from binary mixtures of these building blocks. The identified superstructures are then investigated in terms of their tunable photonic/phononic properties. The dependence of photonic bandgaps on various features of the superstructures such as building block size and shape is studied. Each superstructure is composed of at least four different types of elements, which provides a desirable framework to obtain reconfigurable metamaterials. The calculations show that a binary superstructure of tetrahedral units can result in photonic bandgaps with sizes as large as 27% for material compositions with dielectric constant difference of 15. The new superstructures formed by colloidal molecules expand the existing self-assembly paradigms for colloidal particles. This paper also promotes future experimental and theoretical work for discovering more complex colloidal phases with a higher number of degrees of freedom to be utilized for engineering desired functional materials.

Suppressed electronic contribution in thermal conductivity of Ge2Sb2Se4Te

“…This computing architecture, known as von Neumann, leads to huge traffic jams between the memory and processor, incurring considerable costs in terms of latency and energy 2 , 3 . With the growing demand for data-centric technologies such as artificial intelligence and machine learning, there is a global effort to find alternative computing paradigms to supersede the traditional von Neumann architecture 4 – 7 . Biologically-inspired neuromorphic computing is one of the more promising alternatives to transistor-based technologies that not only offers a significantly higher degree of connectivity between the memory nodes leading to faster computation and less power consumption, but also allows for simultaneous storage and processing of information within the memory cell 8 , 9 .…”

Synthesis of Colloidal Molecules: Recent Advances and Perspectives

“… Possible superstructures and arrays composed of CMs that could be obtained by self‐assembly . Adapted with permission from Ref.…”

“…[77] It was also reportedt hat AX 6 -type CMs can be self-assembled into ordered structures [66] and that DNA-coated CMs with tetragonal geometry provide aw ay to build two new colloidal crystalline lattices:d iamond and pyrochlore. [78] One can thus reasonably assume that more complex superstructures could be self-assembled from other CMs (Figure 4), [79] including chiral ones. This is an exciting challenge that deserves to be met in the near future.A nother target is to expand the panel of reconfigurable CMs, whose geometry could be tuned on demandu nder external stimulus.…”

Hierarchical self-assembly of patchy colloidal platelets

“…Self-assembled finite clusters can be also used as nonspherical building blocks for further -hierarchical -assembly into extended structures and thereby expand the versatility of the original units [18][19][20][21][22]. Colloidal molecules composed of different types of particles, for instance, can be designed to support the assembly of superstructures with target photonic or phononic properties [23]. * Electronic address: carina.karner@univie.ac.at † Electronic address: emanuela.bianchi@tuwien.ac.at…”