Characterizing the dynamics of nanoparticle gel networks demands a spatiotemporal resolution that no single technique can provide. This Perspective describes the opportunities to address this challeng...

Salt modulates gelation in colloidal nanocrystal networks, revealing a universal pathway across time and length scales.

Being intermediate in scale between molecules and colloids, nanoparticles combine characteristics of both. The structure of their self-assembled states combining order and disorder is difficult to qua...

Multilayer assemblies of metal nanoparticles can act as photonic structures, where collective plasmon resonances hybridize with cavity modes to create plasmon-polariton states. For sufficiently strong coupling, plasmon polaritons qualitatively alter the optical properties of light-matter systems, with applications ranging from sensing to solar energy. However, results from experimental studies have raised questions about the role of nanoparticle structural disorder in plasmon-polariton formation and the strength of light-matter coupling in plasmonic assemblies. Understanding how disorder affects optical properties has practical implications since methods for assembling low-defect nanoparticle superlattices are slow and scale poorly. Modeling realistic disorder requires large system sizes, which is challenging using conventional electromagnetic simulations. We employ Brownian dynamics simulations to construct large-scale nanoparticle multilayers with controlled structural order. We investigate their far- and near-field optical response using a superposition T-matrix method with two-dimensional periodic boundary conditions. We find that while structural disorder broadens the polaritonic stop band and the near-field hot-spot distribution, the polariton dispersion and coupling strength remain unaltered. To understand the effects of nanoparticle composition, we consider assemblies with Drude model particles mimicking gold or tin-doped indium oxide (ITO) nanocrystals. Assemblies of ITO nanocrystals, which have lower carrier concentrations, exhibit ultrastrong coupling, in contrast to Au nanoparticle multilayers that display deep strong coupling. Finally, we demonstrate that while computationally efficient mutual polarization method calculations employing the quasistatic approximation modestly overestimate the strength of collective plasmon coupling in these assemblies, they reproduce the polariton dispersion relations determined by electrodynamic simulations.

I cannot participate in systems that require dishonesty as the price of belonging.

After just 100 days, agency scientists say U.S. health institutes are demoralized and have lost essential staff and funding

An NIH insider explains what Republicans are likely to do next, and what we can do

The Trump administration’s attack on scientific research will deeply affect UC Santa Cruz, write three eminent UCSC professors, including one who won a Nobel Prize for her work. Since Donald Trump too...

For decades, universities got billions in federal dollars for research. The relationship was mutually beneficial, until President Trump decided it wasn’t.

Under the compact, participating institutions would “commit meaningful funding to a shared or distributed defense fund” that would “provide immediate and strategic support to any member institution un...

The moves also affect a temporary work program heavily used by STEM graduates

Harvard will not comply with the Trump administration’s demands to dismantle its diversity programming and limit student protests in exchange for its federal funding, University President Alan M. Garb...

New surveillance and punishment systems are a warning to us all

Dr. Ardem Patapoutian says he watches “with deep sadness as the United States’ remarkable scientific enterprise, which took generations of hard work and national investment to build, faces a concerted...

The stakes are high, but the choice should not be difficult.

Import taxes on staples such as microscopes, glassware and computer chips will affect institutions already feeling financial strain.

I teach at University of Michigan's Gerald R. Ford School of Public Policy. Ford's values are worth teaching, not Donald Trump's.

The reasons aren’t clear—and the agency’s director claims the president’s policies haven’t slowed grant awards

Dani Rodrik argues that leaders in both sectors bear a disproportionate responsibility to come to democracy's defense.

Separating carbon dioxide from air, while technically straightforward, is outrageously expensive.

American universities have given the country prosperity and security. The Trump administration’s attack on academic freedom endangers all of that.

As the NIH braces for cuts of up to 5,000 of its 20,000 positions, “people are scrambling and freaking out,” a researcher said.

Trump administration attacks on the National Institutes of Health mean biomedical research will become less ambitious, less competitive and result in fewer breakthroughs.

Scientists rally across the country in response to layoffs and funding cuts ordered by the Trump administration