Molecular-induced chirality transfer to plasmonic lattice modes

ACS nano

Understanding and mastering quantum electrodynamics phenomena is essential to the development of quantum nanophotonics applications. While tailoring of the local vacuum field has been widely used to tune the luminescence rate and directionality of a quantum emitter, its impact on their transition energies is barely investigated and exploited. Fluorescent defects in nanosized diamonds constitute an attractive nanophotonic platform to investigate the Lamb shift of an emitter embedded in a dielectric nanostructure with high refractive index. Using spectral and time-resolved optical spectroscopy of single SiV defects, we unveil blue shifts (up to 80 meV) of their emission lines, which are interpreted from model calculations as giant Lamb shifts. Moreover, evidence for a positive correlation between their fluorescence decay rates and emission line widths is observed, as a signature of modifications not only of the …

Small Methods

Multivariate analysis applied in biosensing greatly improves analytical performance by extracting relevant information or bypassing confounding factors such as nonlinear responses or experimental errors and noise. Plasmonic sensors based on various light coupling mechanisms have shown impressive performance in biosensing by detecting dielectric changes with high sensitivity. In this study, gold nanodiscs are used as metasurface in a Kretschmann setup, and a variety of features from the reflectance curve are used by machine learning to improve sensing performance. The nanostructures of the metasurface generate new plasmonic features, apart from the typical resonance that occurs in the classical Kretschmann mode of a gold thin film, related to the evanescent field beyond total internal reflection. When the engineered metasurface is integrated into a microfluidic chamber, the device provides additional …

Laser & Photonics Reviews

This study describes both experimentally and theoretically an important hitherto undiscovered feature of the scattering of micron‐sized spherical objects when illuminated with highly focused circularly polarized light. This is a regime of high experimental relevance which has not been described in full detail. The experiments are complemented with the analytical formulas explaining the field scattered directed toward the backward hemispace. In particular, it is proven that this field shows a very regular oscillatory dependency with the optical size. This phenomenon is typically hidden in the total scattered field, as the field is scattered much less toward the backward hemisphere than toward the forward one. These regular oscillations are measured experimentally. It is proven that, by analyzing them, it is possible to determine the index of refraction of isolated micron‐sized particles, opening new paths for applications in …

Physical Review X

A direct current through a metal-insulator-metal tunneling junction emits light when surface-plasmon polaritons (SPPs) are excited. Two distinct processes are believed to coexist in this light emission mediated by surface plasmons: inelastic tunneling, where electrons excite SPPs in the insulator gap, and hot-electron radiative decay, which occurs in the electrodes after elastic tunneling. Previous theoretical approaches to study light emission by inelastic tunneling have relied on Bardeen’s approximation where the electronic wave functions are considered only in the barrier of the junction. In this work, we introduce an extension to models of inelastic tunneling by incorporating the full quantum device solution of the Schrödinger equation, which can also account for processes in the metallic electrodes. The extension unveils the existence of long-range correlations of the current density across the barrier and enables us …

Langmuir

In this study, we systematically analyze the surface tension and Hansen solubility parameters (HSPs) of imidazolium-based ionic liquids (ILs) with different anions ([NTf2]−, [PF6]−, [I]−, and [Br]−). These anions are combined with the classical 1-alkyl-3-methyl-substituted imidazolium cations ([CnC1Im]+) and a group of oligoether-functionalized imidazolium cations ([(mPEGn)2Im]+) based on methylated polyethylene glycol (mPEGn). In detail, the influences of the length of the alkyl- and the mPEGn-chain, the anion size, and the water content are investigated experimentally. For [CnC1Im]+-based ILs, the surface tension decreases with increasing alkyl chain length in all cases, but the magnitude of this decrease depends on the size of the anion ([NTf2]− < [PF6]− < [Br]− ≤ [I]−). Molecular dynamics (MD) simulations on [CnC1Im]+-based ILs indicate that these differences are caused by the interplay of charged and …

Bulletin of the American Physical Society

K39. 00003: 2023 APS Fellow. Talk Title: Picocavity-enhanced ultraresolved molecular spectroscopy and microscopy*

Advanced Materials Interfaces

Nanostructured materials that mimic structural coloration in nature can be synthetically created by colloidal self‐assembly. To maximize optical effects, the natural world integrates melanin as a broadband absorber to remove incoherently scattered light. Polydopamine (PDA) is used as a synthetic analog of natural melanin to systematically investigate the influence of absorber quantity and distribution on color saturation in colloidal photonic crystals. The absorbing PDA is integrated into two distinct ways: homogenous colloidal crystals are produced from core–shell particles with incrementally increasing polydopamine shells, and heterogeneous colloidal crystals are formed by co‐assembly of varying ratios of polystyrene (PS) and absorbing PS@PDA particles. The chromaticity is quantified by converting the measured spectra to reconstructed colors in the L*a*b* color sphere to identify structures with optimal color …

Langmuir

Unraveling the two-dimensional (2D) structural ordering of colloidal particles assembled at a flat surface is essential for understanding and optimizing their physical properties. So far, grazing-incidence small-angle X-ray scattering (GISAXS) has been widely used to determine crystallographic information on 2D self-assembled structures of nanosize objects. However, solving the structure of 2D lattices consisting of micrometer (μm)-sized objects still remains a challenge using scattering methods. Here, a model 2D SCALMS (supported catalytically active liquid metal solution) template is fabricated from μm-sized polystyrene (PS) spheres that form a monolayer on top of the flat solid support. GISAXS patterns of the sample were collected for rotation angles around its surface normal in steps of 3°. For every rotation angle, different Bragg-type interference maxima along the out-of-plane (qz) direction were observed. On …

arXiv preprint arXiv:2402.11944

Classical coupled harmonic oscillator models have been proven capable to describe successfully the spectra of many nanophotonic systems where an optical mode couples to a molecular or matter excitation. Although models with distinct coupling terms have been proposed, they are used interchangeably due to their similar results in the weak and strong coupling regimes. However, in the ultrastrong coupling regime, each oscillator model leads to very different predictions. Further, it is important to determine which physical magnitude is associated to each harmonic oscillator of these models in order to reproduce appropriately experimentally measurable quantities in each system. To clarify which classical model must be used for a given experiment, we establish a connection with the quantum description of these systems based on cavity quantum electrodynamics. We show that the proper choice of the classical coupling term depends on the presence or absence of the diamagnetic term in the quantum models and on whether the electromagnetic modes involved in the coupling are transverse or longitudinal. The comparison with quantum models further enables to make the correspondence between quantum operators and classical variables in the oscillator models, in order to extract measurable information of the hybrid modes of the system.

Microfluidics and Nanofluidics

In this study, we show the design and manufacturing of microfluidic deterministic lateral displacement (DLD) devices for sub-micrometer particle separation. For that purpose, devices with pillar gaps of 4 µm and a periodicity of 50 were designed. After photolithographic manufacturing of SU-8 masters with different heights (15 and 30 µm) and vertical sidewalls for soft-lithographic replication with polydimethylsiloxane (PDMS) the influence of flow rate on the separation efficiency of 0.45 and 0.97 µm particles was investigated. The 15 µm devices were operated at 0.125 and 0.5 µl/min sample flow rate and the 30 µm devices at 0.5 and 2.0 µl/min, respectively. Excellent separation efficiencies were observed for both device heights at the lower sample flow rates, while separation efficiencies decreased at the respective higher sample flow rates. The decrease in separation efficiency was attributed to deformation of the soft …

Advanced Materials

Continuous gradients in self-assembled materials can provide functionality exceeding that of the homogenous case. In article number 2208745, Markus Retsch and co-workers present a synthesis method that provides gradient size distributions via a controlled extraction emulsion process (CrEEP). The high degree of control allows the fabrication of a continuous-gradient photonic glass with enhanced broadband reflectance.

Research data supporting "Probing optical anapoles with fast electron beams" (https://www.nature.com/articles/s41467-023-43813-y) | DIGITAL.CSIC Skip navigation Logo pequeño DigitalCISC Producción CSIC Áreas e Institutos Navegar ítems por: Fecha Publicación Autor Título Palabras Clave Autor con perfil Proyecto de investigación Grupo de investigación Agencia Financiadora Fecha Envío Pasarela Estadísticas Contacto Servicios Mi DIGITAL.CSIC Suscripciones Editar perfil 1.DIGITAL.CSIC 2.Ciencia y Tecnología de Materiales 3.Centro de Física de Materiales (CFM) 4.(CFM) Conjuntos de datos Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/355156 COMPARTIR / EXPORTAR: logo share SHARE BASE Comparte tu historia de Acceso Abierto Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE Refman EndNote Bibtex …

Langmuir

Colloidal lithography utilizes self-assembled particle monolayers as lithographic masks to fabricate arrays of nanostructures by combination of directed evaporation and etching steps. This process provides complex nanostructures over macroscopic areas in a simple, convenient, and parallel fashion without requiring clean-room infrastructure and specialized equipment. The appeal of the method comes at the price of imperfections impairing the optical quality, especially for arrayed nanostructures relying on well-ordered lattices. Imperfections are often generically mentioned to rationalize the discrepancy between experimental and simulated resonances. Yet, little attention is given to detailed structure–property relationships connecting typical defects directly with the optical properties. Here, we use a correlative approach to connect nano- and microscopic defects occurring from the colloidal lithography process with …

Nanophotonics

The surface-response formalism (SRF), where quantum surface-response corrections are incorporated into the classical electromagnetic theory via the Feibelman parameters, serves to address quantum effects in the optical response of metallic nanostructures. So far, the Feibelman parameters have been typically obtained from many-body calculations performed in the long-wavelength approximation, which neglects the nonlocality of the optical response in the direction parallel to the metal–dielectric interface, thus preventing to address the optical response of systems with extreme field confinement. To improve this approach, we introduce a dispersive SRF based on a general Feibelman parameter d ⊥(ω, k ‖), which is a function of both the excitation frequency, ω, and the wavenumber parallel to the planar metal surface, k ‖. An explicit comparison with time-dependent density functional theory (TDDFT) results …

Advanced Engineering Materials

A novel strategy for manufacturing of the main insulation of high‐voltage rotating machines is presented. The developed process is based on established electrostatic powder coating equipment. Using complete automation enables the precise and reproducible application of homogeneous powder coating layers. Individual layers can be stacked by process repetitions to achieve a desired layer thickness. This coating strategy alters the particle deposition process by introducing additional capillary bridges that significantly increase powder adhesion. A systematic parameter study is performed to provide process–structure relations connecting various process parameters with the resultant coating thickness and homogeneity. The parameters of the developed coating process are iteratively improved to maximize coating homogeneity and minimize defect density, the most critical parameters in high‐voltage insulation …

ACS photonics

The spin and orbital angular momentum carried by electromagnetic pulses open new perspectives to control nonlinear processes in light–matter interactions, with a wealth of potential applications. In this work, we use time-dependent density functional theory (TDDFT) to study the nonlinear optical response of a free-electron plasmonic nanowire to an intense, circularly polarized electromagnetic pulse. In contrast to the well-studied case of the linear polarization, we find that the nth harmonic optical response to circularly polarized light is determined by the multipole moment of order n of the induced nonlinear charge density that rotates around the nanowire axis at the fundamental frequency. As a consequence, the frequency conversion in the far field is suppressed, whereas electric near fields at all harmonic frequencies are induced in the proximity of the nanowire surface. These near fields are circularly polarized …

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Macromolecular Materials and Engineering

Liquid‐infused surfaces exhibit remarkable repellency properties toward water, oils, and complex fluids and are widely applied to maintain clean, operational, and high‐performing surfaces in various fields, from the biomedical sector to marine infrastructure. Polydopamine (PDA) forms an ideal base layer for the development of such coatings as it adheres to virtually any substrate and can be chemically modified via amino‐containing molecules to adjust the surface properties. Here, strategies are explored to increase the mechanical stability of such coatings by i) incorporating imidazole during film formation to increase crosslinking, and ii) formation of a composite consisting of the organic PDA and an inorganic siliceous porous coating by infiltration of a preformed porous silica layer with PDA. Both strategies exhibit improved resistance to tangential shear assessed by a sandpaper abrasion test and to dynamic …

ACS Photonics

Metasurfaces have revolutionized optical biosensing and diagnostic assays due to their sensitivity, compactness, and label-free operation. However, metasurface applications in analyzing complex biological systems and quantum bioscience phenomena remain scarce. In this Perspective, we discuss current developments in metasurface biosensors and propose promising future applications for probing or adopting quantum bioscience effects and improving spatial omics analysis in live cells and tissues. We discuss the capabilities of the current metasurface platforms for monitoring relevant biomarkers of viral diseases, neurodegenerative diseases, and cancers. Metasurface-empowered examination of cell morphology and secretome, virus detection, and tissue imaging can improve the accuracy of early diagnosis. Furthermore, we review device-integration approaches for point-of-care testing settings that could …

ACS photonics

In this Article, we present a series of novel laser-written liquid crystal (LC) devices for aberration control for applications in beam shaping or aberration correction through adaptive optics. Each transparent LC device can correct for a chosen aberration mode with continuous greyscale tuning up to a total magnitude of more than 2π radians phase difference peak to peak at a wavelength of λ = 660 nm. For the purpose of demonstration, we present five different devices for the correction of five independent Zernike polynomial modes (although the technique could readily be used to manufacture devices based on other modes). Each device is operated by a single electrode pair tuned between 0 and 10 V. These devices have potential as a low-cost alternative to spatial light modulators for applications where a low-order aberration correction is sufficient and transmissive geometries are required.

ACS Photonics

The chirality of an object can be studied by measuring the circular dichroism, that is, the difference in absorption of light with different helicity. The chiral optical response of an object, however, can have two different origins. On the one hand, it can be linked to the chiral geometry of the object. On the other hand, it can be linked to the chiral material from which the object is made. Whereas previously no distinction between the two contributions could be made, we report here a computational approach that allows us to separate these two contributions to the circular dichroism of an object. We consider separately the case where geometry-related resonances affect the optical response and the case where they are absent. In both cases, we find the circular dichroism to be easily decomposable if a geometrically achiral object has an absorption spectrum similar to that of the chiral object under investigation. Furthermore, in …

ACS Photonics

The Ising machine (IM) has emerged as a promising tool for tackling nondeterministic polynomial-time hard combinatorial optimization problems in real-world applications. Among various types of IMs, optoelectronic IMs based on electro-optical (EO) modulators stand out as an impressive platform for Ising computations. They offer a simple and stable architecture, with the EO modulator providing a natural inline nonlinear transfer function for the Ising model. However, integrated optoelectronic IMs have not been demonstrated until now, and exploring large-scale computations within the constraints of digital hardware resources remains an open challenge for these systems. In this paper, an integrated optoelectronic IM based on a thin-film lithium niobate (TFLN) photonic chip is presented, in conjunction with a sparse matrix–vector multiplication algorithm embedded in a field-programmable gate array that optimizes …

ACS photonics

Optical microcavities confine light to wavelength-scale volumes and are a key component for manipulating and enhancing the interaction of light, vacuum states, and matter. Current microcavities are constrained to a small number of spatial mode profiles. Imaging cavities can accommodate complicated modes but require an externally preshaped input. Here, we experimentally demonstrate a visible-wavelength, metasurface-based holographic microcavity that overcomes these limitations. The micrometer-scale metasurface cavity fulfills the round-trip condition for a designed mode with a complex-shaped intensity profile and thus selectively enhances light that couples to this mode, achieving a spectral bandwidth of 0.8 nm. By imaging the intracavity mode, we show that the holographic mode changes quickly with the cavity length and that the cavity displays the desired spatial mode profile only close to the design …

ACS Photonics

Metasurface integrated waveguide couplers provide a promising pathway toward advanced manipulation of free-space light for guided wave coupling, such as polarization routing, mode-selective coupling, and wavelength (de)multiplexing. However, it is a great challenge to manipulate the guided wave polarization state to be completely decoupled from the polarization of incident light. Here, an adjoint-based topology optimization method is employed to inversely design a freeform metasurface for unidirectionally coupling free-space light into customized waveguide mode, with the capabilities of polarization manipulation and guided mode selection. An arbitrary transverse magnetic or transverse electric eigenmode can be unidirectionally excited for any incident polarization state conditions, with the maximum polarization-rotated mode purity and unidirectional coupling efficiency approaching 90.97 and 43 …

ACS Photonics

Stimulated emission depletion (STED) microscopy is a powerful super-resolution imaging technique for investigating the subcellular structure of biological samples in all three spatial dimensions. Its application to thick specimens is challenging, however, as sample-induced optical aberrations distort the intricate phase patterns of the STED beams and, consequently, their focal intensity distribution. Notably, the central intensity minimum, which is essential for resolution enhancement, is lifted at larger sample depths. Here we present a technique for correction of STED beam aberrations featuring minimal light exposure of the samples to avoid photobleaching and phototoxicity. We quantify STED beam aberrations by using modal wavefront sensing with spatial light modulators (SLMs) as adaptive optics (AO) elements based on reflection imaging of gold beads immobilized at the top and bottom surfaces enclosing the …

ACS Photonics

The study of electromagnetic scattering in optics and nanophotonics is crucial for understanding complex nanostructures and optical devices. However, numerical analysis of scattering spectra, even for simple shape nanocavities, presents significant computational challenges. This paper focuses on simplifying the simulation process by utilizing system symmetries and the separation of variables, which reduces the dimension of the problem. Specifically, we present a practical guide to efficiently simulate linear and nonlinear scattering problems in COMSOL Multiphysics for axisymmetric objects. This includes computing the scattering cross-section, multipolar decomposition, optical forces, and second harmonic generation (SHG). We show that by reducing the calculation time we are able to analyze the generation spectra of SH under varying geometrical parameters of nanoantennas across a broad range. Additionally …

ACS Photonics

Subwavelength grating (SWG) waveguides are attractive for building photonic integrated circuits due to their flexible dispersion engineering. These SWG waveguides are typically formed by a chain of nanoparticles with an electric dipole (ED)-like profile, which have to be nonresonant in order to homogenize the SWG waveguide as an effective strip waveguide. Here, we report the counterpart supported by the magnetic dipole (MD) mode of silicon nanoparticles. Benefiting from the special circular electric field of the MD mode, the MD-based SWG waveguide allows the construction of a tapered coupler, 90° bending waveguide, and directional coupler with more compact footprints than the counterparts composed by traditional ED-based SWG waveguides.

ACS Photonics

Optical wireless communication has garnered significant interest, yet its inherent transparency poses a formidable challenge to ensure communication security. Optical encryption communication (OEC) emerges as a potential remedy; however, its widespread adoption is hindered by its intricate design and high operational complexity. Herein, we propose an OEC scenario employing self-powered dual-polarity Dember photodetectors (PDs) composed by a sandwich configuration of ITO/MASnI3/Ag. The highly manipulated photonic responses (i.e., direct optical absorption and localized surface plasmon resonance) together with the strong Dember effect by perovskite material empower the unbiased PDs to exhibit the reverse photocurrents (i.e., dual polarity) across a broad wavelength band, which shows a strong robustness against the variations of light source, material composition, and geometric setup. Moreover …

ACS Photonics

Compact, low-noise microwave oscillators are required throughout a wide range of applications such as radar systems, wireless networks, and frequency metrology. Optical frequency division via an optical frequency comb provides a powerful tool for low-noise microwave signal generation. Here, we experimentally demonstrate an optical reference down to 26 GHz frequency division based on the dissipative Kerr soliton comb, which is generated on a CMOS-compatible, high-index doped silica glass platform. The optical reference is generated through two continuous wave lasers locked to an ultralow expansion cavity. The dissipative Kerr soliton comb with a repetition rate of 26 GHz acts as a frequency divider to derive an ultralow-noise microwave oscillator, with a phase noise level of −101.3 dBc/Hz at a 100 Hz offset frequency and −132.4 dBc/Hz at a 10 kHz offset frequency. Furthermore, the Allan deviation of the …

ACS Photonics

In this work, we comprehensively review Mie resonator-based and nonlocal resonant metasurfaces working in the reflection configuration for color printing applications, with particular attention to high observation angle applications. While Mie resonator-based metasurfaces are found to be simple to design and present low sensitivity to the observation angle, they present the drawback of low color saturation. By contrast, square lattice photonic crystal waveguide-based metasurfaces show very selective spectral responses, yielding pure colors but with high selectivity on the observation angle. In order to harness the exceptional color-filtering properties of photonic crystal waveguides and maintain the desired spectral response under oblique angles of observation, a rectangular lattice for the crystal structure is proposed. We provide design rules and examples in order to produce angularly robust, vivid colors at any …

ACS Photonics

Spaceplates are nonlocal optical devices with the potential to reduce the form factor of optical systems, but current implementations are limited in performance and ability to correct for optical aberrations. We introduce a new class of multifunctional spaceplates, designed using gradient-based freeform optimization, which exhibit exceptional efficiencies, compression ratios, and aberration correcting capabilities. We show that such spaceplates can serve as correctors for metasurfaces and refractive optical elements, and we demonstrate that multifunctional spaceplates can extend to support multispectral, Petzval field curvature, and spherical aberration correction. We anticipate that these spaceplate concepts will enable the realization of ultracompact optical systems.

ACS Photonics

We report on how observation of the Goos–Hänchen (GH) shift can be used to spatially resolve the transverse magneto-optical Kerr effect (TMOKE) enhancement in all-nickel magnetoplasmonic crystals (MPCs). First, the excitation of surface plasmons in the MPCs leads to a 15.3 μm (18λ) GH shift. Then, in the presence of a transverse magnetic field, the modulation of the lateral spatial intensity distribution of the reflected light [TMOKE(x)], caused by the GH shift, reaches 4.7% in the experiment. The spatially resolved TMOKE(x) values are several times higher compared to those from conventional TMOKE measurements in the MPCs. The concept of the spatially resolved magneto-optical effects under GH shift can be further extended to other magnetophotonic nanodevices for additional enhancing magneto-optical effects, sensing, and light modulation applications.

ACS Photonics

Quasi-two-dimensional (quasi-2D) perovskites are promising as a gain medium for laser applications owing to their inherent multiple quantum wells and remarkable stability. Meanwhile, thermal evaporation deposition is a promising complementary approach to further advance the commercialization of perovskite-based lasers. However, investigations into thermally evaporated perovskite lasers are scarce, and their performance is significantly inferior to that of their solution-processed counterparts. Herein, we demonstrate a high-quality thermally evaporated quasi-2D perovskite film with excellent gain properties via a tri-source co-evaporation strategy. The carrier dynamics and gain nature of the perovskite film are revealed with a long gain lifetime of 66.5 ps. The net modal gain is up to 1071 cm–1, which is afforded by rapid carrier accumulation (<0.25 ps) and facile buildup of population inversion. As a result …

ACS Photonics

Matrix computations are at the heart of scientific computing, especially in models involving large-scale linear systems. As the scale and complexity of the problems grow, energy-efficient matrix computation becomes critical in these applications. Meanwhile, the advantages of miniaturizing conventional digital electronic processors, predicted by the Dennard scaling, diminish in post-Moore’s law era. Analogue photonic devices based on passive and high-throughput interconnects are becoming promising alternatives as next-generation energy-efficient computing units. However, the limited reconfigurability and precision of an analogue photonic computing device make it unsuitable for scientific computing applications. Here, we report a general-purpose analogue photonic matrix processing unit (MPU) based on coherent analogue photonic cores, which perform signed multiplications, with reconfigurability and memory …

ACS Photonics

Energetic and optical properties of plasmonic nanocrystals strongly depend on their sizes, shapes, and composition. Whereas the use of plasmonic nanoparticles in biotesting has become routine, applications of plasmonics in energy are still early in development. Here, we investigate hot-electron (HE) generation and related electromagnetic effects in both mono- and bimetallic nanorods (NRs) and focus on a promising type of bimetallic nanocrystal–core–shell Au–Ag nanorods. The spectra of the NRs are broadband, highly tunable with their geometry, and exhibit few plasmon resonances. In this work, we provide a new quantum formalism describing the HE generation in bimetallic nanostructures. Interestingly, we observe that the HE generation rate at the UV plasmon resonance of Au–Ag NRs appears to be very high. These HEs are highly energetic and suitable for carbon-fuel reactions. Simultaneously, the HE …

ACS photonics

Surface-enhanced spectroscopy techniques are the method-of-choice to characterize adsorbed intermediates occurring during electrochemical reactions, which are crucial in realizing a green and sustainable future. Characterizing species with low coverage or short lifetimes has so far been limited by low signal enhancement. Recently, single-band metasurface-driven surface-enhanced infrared absorption spectroscopy (SEIRAS) has been pioneered as a promising technology to monitor a single vibrational mode during electrochemical CO oxidation. However, electrochemical reactions are complex, and their understanding requires the simultaneous monitoring of multiple adsorbed species in situ, hampering the adoption of nanostructured electrodes in spectro-electrochemistry. Here, we develop a multi-band nanophotonic-electrochemical platform that simultaneously monitors in situ multiple adsorbed species …

ACS Photonics

Matrix computations are at the heart of scientific computing, especially in models involving large-scale linear systems. As the scale and complexity of the problems grow, energy-efficient matrix computation becomes critical in these applications. Meanwhile, the advantages of miniaturizing conventional digital electronic processors, predicted by the Dennard scaling, diminish in post-Moore’s law era. Analogue photonic devices based on passive and high-throughput interconnects are becoming promising alternatives as next-generation energy-efficient computing units. However, the limited reconfigurability and precision of an analogue photonic computing device make it unsuitable for scientific computing applications. Here, we report a general-purpose analogue photonic matrix processing unit (MPU) based on coherent analogue photonic cores, which perform signed multiplications, with reconfigurability and memory …

ACS Photonics

Exciton-polaritons (EP), half-light half-matter quasiparticles that form in optical cavities, are attractive platforms for creating macroscopic coherent states such as Bose–Einstein condensation (BEC). EPs based on organic molecules are of particular interest for realizing such states at room temperature while offering the promise of synthetic tunability. However, the demonstrations of such condensates have been limited to a few specific molecular systems (Keeling et al. Bose-Einstein condensation of exciton-polaritons in organic microcavities. Annual Review of Physical Chemistry 2020, 71, 435–459). Here we report a universal platform for realizing molecular polariton condensates using commercial dyes that solve long-standing material challenges. This solution is made possible using a new and programmable molecular material called small-molecule, ionic isolation lattices (SMILES) with the potential to incorporate …