Integrated photonics will play a key role in quantum systems as they grow from few-qubit prototypes to tens of thousands of qubits. The underlying optical quantum technologies can only be realized through the integration of these components onto quantum photonic integrated circuits (QPICs) with accompanying electronics. In the last decade, remarkable advances in quantum photonic integration have enabled table-top experiments to be scaled down to prototype chips with improvements in efficiency, robustness, and key performance metrics. These advances have enabled integrated quantum photonic technologies combining up to 650 optical and electrical components onto a single chip that are capable of programmable quantum information processing, chip-to-chip networking, hybrid quantum system integration, and high-speed communications. In this roadmap article, we highlight the status, current and future challenges, and emerging technologies in several key research areas in integrated quantum photonics, including photonic platforms, quantum and classical light sources, quantum frequency conversion, integrated detectors, and applications in computing, communications, and sensing. With advances in materials, photonic design architectures, fabrication and integration processes, packaging, and testing and benchmarking, in the next decade we can expect a transition from single- and few-function prototypes to large-scale integration of multi-functional and reconfigurable devices that will have a transformative impact on quantum information science and engineering.
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JPhys Photonics is an innovative open access journal highlighting significant and exciting advances in research into the properties and applications of light. The scope spans the full breadth of fundamental and applied optics research, bringing together scientists from a range of disciplines, with a particular focus on interdisciplinary and multidisciplinary studies.
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Galan Moody et al 2022 J. Phys. Photonics 4 012501
Chien-Chung Lin et al 2023 J. Phys. Photonics 5 042502
Micro light-emitting diode (micro-LED) will play an important role in the future generation of smart displays. They are found very attractive in many applications, such as maskless lithography, biosensor, augmented reality (AR)/mixed reality etc, at the same time. A monitor that can fulfill saturated color rendering, high display resolution, and fast response time is highly desirable, and the micro-LED-based technology could be our best chance to meet these requirements. At present, semiconductor-based red, green and blue micro-LED chips and color-conversion enhanced micro-LEDs are the major contenders for full-color high-resolution displays. Both technologies need revolutionary ways to perfect the material qualities, fabricate the device, and assemble the individual parts into a system. In this roadmap, we will highlight the current status and challenges of micro-LED-related issues and discuss the possible advances in science and technology that can stand up to the challenges. The innovation in epitaxy, such as the tunnel junction, the direct epitaxy and nitride-based quantum wells for red and ultraviolet, can provide critical solutions to the micro-LED performance in various aspects. The quantum scale structure, like nanowires or nanorods, can be crucial for the scaling of the devices. Meanwhile, the color conversion method, which uses colloidal quantum dot as the active material, can provide a hassle-free way to assemble a large micro-LED array and emphasis the full-color demonstration via colloidal quantum dot. These quantum dots can be patterned by porous structure, inkjet, or photo-sensitive resin. In addition to the micro-LED devices, the peripheral components or technologies are equally important. Microchip transfer and repair, heterogeneous integration with the electronics, and the novel 2D material cannot be ignored, or the overall display module will be very power-consuming. The AR is one of the potential customers for micro-LED displays, and the user experience so far is limited due to the lack of a truly qualified display. Our analysis showed the micro-LED is on the way to addressing and solving the current problems, such as high loss optical coupling and narrow field of view. All these efforts are channeled to achieve an efficient display with all ideal qualities that meet our most stringent viewing requirements, and we expect it to become an indispensable part of our daily life.
Giovanni Volpe et al 2023 J. Phys. Photonics 5 022501
Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in the life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nano-particle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration.
Nemanja Jovanovic et al 2023 J. Phys. Photonics 5 042501
Photonic technologies offer numerous functionalities that can be used to realize astrophotonic instruments. The most spectacular example to date is the ESO Gravity instrument at the Very Large Telescope in Chile that combines the light-gathering power of four 8 m telescopes through a complex photonic interferometer. Fully integrated astrophotonic devices stand to offer critical advantages for instrument development, including extreme miniaturization when operating at the diffraction-limit, as well as integration, superior thermal and mechanical stabilization owing to the small footprint, and high replicability offering significant cost savings. Numerous astrophotonic technologies have been developed to address shortcomings of conventional instruments to date, including for example the development of photonic lanterns to convert from multimode inputs to single mode outputs, complex aperiodic fiber Bragg gratings to filter OH emission from the atmosphere, complex beam combiners to enable long baseline interferometry with for example, ESO Gravity, and laser frequency combs for high precision spectral calibration of spectrometers. Despite these successes, the facility implementation of photonic solutions in astronomical instrumentation is currently limited because of (1) low throughputs from coupling to fibers, coupling fibers to chips, propagation and bend losses, device losses, etc, (2) difficulties with scaling to large channel count devices needed for large bandwidths and high resolutions, and (3) efficient integration of photonics with detectors, to name a few. In this roadmap, we identify 24 key areas that need further development. We outline the challenges and advances needed across those areas covering design tools, simulation capabilities, fabrication processes, the need for entirely new components, integration and hybridization and the characterization of devices. To realize these advances the astrophotonics community will have to work cooperatively with industrial partners who have more advanced manufacturing capabilities. With the advances described herein, multi-functional integrated instruments will be realized leading to novel observing capabilities for both ground and space based platforms, enabling new scientific studies and discoveries.
Yue Zhou et al 2024 J. Phys. Photonics 6 025013
Cadmium sulfide (CdS) pigments have degraded in several well-known artworks, but the influence of pigment properties and environmental conditions on the degradation process have yet to be fully understood. Traditional non-destructive analysis techniques primarily focus on macroscopic degradation, whereas microscopic information is typically obtained with invasive techniques that require sample removal. Here, we demonstrate the use of pump-probe microscopy to nondestructively visualize the three-dimensional structure and degradation progress of CdS pigments in oil paints. CdS pigments, reproduced following historical synthesis methods, were reproduced as oil paints and artificially aged by exposure to high relative humidity and light. The degradation of CdS to CdSO4·xH2O was confirmed by both FTIR (Fourier-transform infrared) and XPS (x-ray photoelectron spectroscopy) experiments. During the degradation process, optical pump-probe microscopy was applied to track the degradation progress in single grains, and volumetric imaging revealed early CdS degradation of small particles and on the surface of large particles. This indicates that the particle dimension influences the extent and evolution of degradation of historical CdS. In addition, the pump-probe signal decrease in degraded CdS is observable before visible changes to the eye, demonstrating that pump-probe microscopy is a promising tool to detect early-stage degradation in artworks.
Kun Yin et al 2021 J. Phys. Photonics 3 022010
Virtual reality (VR) and augmented reality (AR) are revolutionizing the ways we perceive and interact with various types of digital information. These near-eye displays have attracted significant attention and efforts due to their ability to reconstruct the interactions between computer-generated images and the real world. With rapid advances in optical elements, display technologies, and digital processing, some VR and AR products are emerging. In this review paper, we start with a brief development history and then define the system requirements based on visual and wearable comfort. Afterward, various VR and AR display architectures are analyzed and evaluated case by case, including some of the latest research progress and future perspectives.
Stefania Castelletto and Alberto Boretti 2020 J. Phys. Photonics 2 022001
Silicon carbide has recently surged as an alternative material for scalable and integrated quantum photonics, as it is a host for naturally occurring color centers within its bandgap, emitting from the UV to the IR even at telecom wavelength. Some of these color centers have been proved to be characterized by quantum properties associated with their single-photon emission and their coherent spin state control, which make them ideal for quantum technology, such as quantum communication, computation, quantum sensing, metrology and can constitute the elements of future quantum networks. Due to its outstanding electrical, mechanical, and optical properties which extend to optical nonlinear properties, silicon carbide can also supply a more amenable platform for photonics devices with respect to other wide bandgap semiconductors, being already an unsurpassed material for high power microelectronics. In this review, we will summarize the current findings on this material color centers quantum properties such as quantum emission via optical and electrical excitation, optical spin polarization and coherent spin control and manipulation. Their fabrication methods are also summarized, showing the need for on-demand and nanometric control of the color centers fabrication location in the material. Their current applications in single-photon sources, quantum sensing of strain, magnetic and electric fields, spin-photon interface are also described. Finally, the efforts in the integration of these color centers in photonics devices and their fabrication challenges are described.
Sylvain Gigan et al 2022 J. Phys. Photonics 4 042501
The last decade has seen the development of a wide set of tools, such as wavefront shaping, computational or fundamental methods, that allow us to understand and control light propagation in a complex medium, such as biological tissues or multimode fibers. A vibrant and diverse community is now working in this field, which has revolutionized the prospect of diffraction-limited imaging at depth in tissues. This roadmap highlights several key aspects of this fast developing field, and some of the challenges and opportunities ahead.
Jian Lin Su et al 2024 J. Phys. Photonics 6 035010
Metasurface has garnered extensive attention across multiple disciplines owing to its profound capability in electromagnetic (EM) manipulations. To determine its EM characteristics accurately, full-wave simulations are essential. These simulations necessitate significant amounts of time and memory resources, hindering the efficiency of the design process. In this article, we propose MetaPhyNet, a novel physics-driven neural network based on temporal coupled-mode theory (CMT) to address the challenges of low efficiency and high memory consumption in large-scale metasurface design. In the proposed approach, a surrogate model is developed to achieve rapid prediction of the EM responses of ultra-large-scale metasurfaces. In comparison with the full-wave EM simulation, the proposed model reduces the simulation time of the ultra-large-scale metasurface by up to two orders of magnitude and the memory consumption by more than two orders of magnitude. Our proposed approach aims to enhance the efficiency and intelligence in metasurface design by leveraging the principles of CMT within a neural network framework. Through this innovative integration of physics-based modeling and machine learning, we seek to achieve significant advancements in the design efficiency of metasurfaces. We apply the proposed model to optimize the design of two metasurface absorbers to showcase the effectiveness of our proposed approach. Simulations and experimental results are provided to demonstrate the value and impact of our approach in addressing existing challenges in full-wave EM simulation-based design optimizations of metasurfaces.
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Lucas Eisenbach et al 2024 J. Phys. Photonics 6 035015
Within this work we demonstrate the highly efficient nonlinear spectral broadening and subsequent temporal compression of 1.49 mJ pulses at 101 kHz repetition rate from an ultrafast thulium-doped fiber laser system employing a gas-filled multi-pass cell (MPC). To achieve spectral broadening, we use a krypton and helium-filled Herriott-type MPC with highly reflective broadband dielectric mirrors. The spectrally broadened pulses are subsequently compressed using fused-silica plates, resulting in a pulse duration of 20 fs and an overall excellent transmission of 96%. Furthermore, the beam quality is preserved up to the maximum output power of 144 W. It provides, to the best of our knowledge, the highest average power with few-cycle pulses at 2 µm wavelength with almost 10 times more pulse energy and 3 times more average power than previous 2 µm MPCs, enabling future secondary source experiments.
Noor Afsary et al 2024 J. Phys. Photonics 6 035014
High-speed and energy-efficient electro-optic (EO) switches are crucial for next-generation data communication systems. This paper presents a novel EO switch utilizing a multimode interference (MMI) coupler-based approach on a lithium-niobate (LiNbO3) platform. The switch is designed with Bezier S-bend waveguides, leading to a significant reduction in bending loss to 0.18 dB. This Bezier-bend EO switch shows an excess loss of 0.33 dB and crosstalk of −20.44 dB for the bar port switching, while the cross port switching exhibits an excess loss of 0.64 dB and crosstalk of −13.66 dB. Applying a 3.27 V voltage achieves a balanced splitting ratio of 29:29:29 between the three outputs. The length of this EO switch is 4.09 mm, which requires 4.1 V to create a phase shift, showing a voltage efficiency of 1.68 V.cm. This paper presents a promising pathway for a novel EO switch design and introduces improved signal management for next-generation computing systems.
Benedetto Ardini et al 2024 J. Phys. Photonics 6 035013
Hyperspectral imaging (HSI) has emerged as an effective tool to obtain spatially resolved spectral information of artworks by combining optical imaging with spectroscopy. This technique has proven its efficacy in providing valuable information both at the large and microscopic scale. Interestingly, the macro scale has yet to be thoroughly investigated using this technology. While standard HSI methods include the use of spatial or spectral filters, alternative methods based on Fourier-transform interferometry have also been utilised. Among these, a hyperspectral camera employing a birefringent common-path interferometer, named TWINS, has been developed, showing a high robustness and versatility. In this paper, we propose the combination of TWINS with a macro imaging system for the study of cultural heritage (CH). We will show how the macro-HSI system was designed, and we will demonstrate its efficient capabilities to collect interferometric images with high visibility and good signal of both reflectance and fluorescence on the same field of view, even on non-flat samples. Our hyperspectral camera for macro studies of both reflectance and fluorescence data is a completely new asset in the CH panorama and beyond. The relevance of the macro technology is demonstrated in two case studies, aiding in the analysis of biofilms on stone samples and of the degradation of dyed textiles.
Caterina Czibula et al 2024 J. Phys. Photonics 6 035012
Brillouin light scattering spectroscopy is applied to study the micromechanics of cellulosic viscose fibers, one of the commercially most important, man-made biobased fibers. Using an equal angle scattering geometry, we provide a thorough description of the procedure to determine the complete transversely isotropic elastic stiffness tensor. From the stiffness tensor the engineering-relevant material parameters such as Young's moduli, shear moduli, and Poisson's ratios in radial and axial fiber direction are evaluated. The investigated fiber type shows that, at ideal conditions, the material exhibits optical waveguide properties resulting in spontaneous Brillouin backscattering which can be used to obtain additional information from the Brillouin spectra, enabling the measurement of two different scattering processes and directions with only one scattering geometry.
Sina Aghili et al 2024 J. Phys. Photonics 6 035011
We exploit InSb's magnetic-induced optical properties to design THz sub-wavelength antennas that actively tune the radiative decay rates of dipole emitters at their proximity. The proposed designs include a spherical InSb antenna and a cylindrical Si-InSb hybrid antenna demonstrating distinct behaviors. The former dramatically enhances both radiative and non-radiative decay rates in the epsilon-near-zero region due to the dominant contribution of the Zeeman-splitting electric octupole mode. The latter realizes significant radiative decay rate enhancement via magnetic octupole mode, mitigating the quenching process and accelerating the photon production rate. A deep-learning-based optimization of emitter positioning further enhances the quantum efficiency of the proposed hybrid system. These novel mechanisms are promising for tunable THz single-photon sources in integrated quantum networks.
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Pietro Ricci et al 2024 J. Phys. Photonics 6 022001
Cutting-edge methodologies and techniques are required to understand complex neuronal dynamics and pathological mechanisms. Among them, optical tools stand out due to their combination of non-invasiveness, speed, and precision. Examples include optical microscopy, capable of characterizing extended neuronal populations in small vertebrates at high spatiotemporal resolution, or all-optical electrophysiology and optogenetics, suitable for direct control of neuronal activity. However, these approaches necessitate progressively higher levels of accuracy, efficiency, and flexibility of illumination for observing fast entangled neuronal events at a millisecond time-scale over large brain regions. A promising solution is the use of acousto-optic deflectors (AODs). Based on exploiting the acousto-optic effects, AODs are high-performance devices that enable rapid and precise light deflection, up to MHz rates. Such high-speed control of light enables unique features, including random-access scanning or parallelized multi-beam illumination. Here, we survey the main applications of AODs in neuroscience, from fluorescence imaging to optogenetics. We also review the theory and physical mechanisms of these devices and describe the main configurations developed to accomplish flexible illumination strategies for a better understanding of brain function.
Nemanja Jovanovic et al 2023 J. Phys. Photonics 5 042501
Photonic technologies offer numerous functionalities that can be used to realize astrophotonic instruments. The most spectacular example to date is the ESO Gravity instrument at the Very Large Telescope in Chile that combines the light-gathering power of four 8 m telescopes through a complex photonic interferometer. Fully integrated astrophotonic devices stand to offer critical advantages for instrument development, including extreme miniaturization when operating at the diffraction-limit, as well as integration, superior thermal and mechanical stabilization owing to the small footprint, and high replicability offering significant cost savings. Numerous astrophotonic technologies have been developed to address shortcomings of conventional instruments to date, including for example the development of photonic lanterns to convert from multimode inputs to single mode outputs, complex aperiodic fiber Bragg gratings to filter OH emission from the atmosphere, complex beam combiners to enable long baseline interferometry with for example, ESO Gravity, and laser frequency combs for high precision spectral calibration of spectrometers. Despite these successes, the facility implementation of photonic solutions in astronomical instrumentation is currently limited because of (1) low throughputs from coupling to fibers, coupling fibers to chips, propagation and bend losses, device losses, etc, (2) difficulties with scaling to large channel count devices needed for large bandwidths and high resolutions, and (3) efficient integration of photonics with detectors, to name a few. In this roadmap, we identify 24 key areas that need further development. We outline the challenges and advances needed across those areas covering design tools, simulation capabilities, fabrication processes, the need for entirely new components, integration and hybridization and the characterization of devices. To realize these advances the astrophotonics community will have to work cooperatively with industrial partners who have more advanced manufacturing capabilities. With the advances described herein, multi-functional integrated instruments will be realized leading to novel observing capabilities for both ground and space based platforms, enabling new scientific studies and discoveries.
Chien-Chung Lin et al 2023 J. Phys. Photonics 5 042502
Micro light-emitting diode (micro-LED) will play an important role in the future generation of smart displays. They are found very attractive in many applications, such as maskless lithography, biosensor, augmented reality (AR)/mixed reality etc, at the same time. A monitor that can fulfill saturated color rendering, high display resolution, and fast response time is highly desirable, and the micro-LED-based technology could be our best chance to meet these requirements. At present, semiconductor-based red, green and blue micro-LED chips and color-conversion enhanced micro-LEDs are the major contenders for full-color high-resolution displays. Both technologies need revolutionary ways to perfect the material qualities, fabricate the device, and assemble the individual parts into a system. In this roadmap, we will highlight the current status and challenges of micro-LED-related issues and discuss the possible advances in science and technology that can stand up to the challenges. The innovation in epitaxy, such as the tunnel junction, the direct epitaxy and nitride-based quantum wells for red and ultraviolet, can provide critical solutions to the micro-LED performance in various aspects. The quantum scale structure, like nanowires or nanorods, can be crucial for the scaling of the devices. Meanwhile, the color conversion method, which uses colloidal quantum dot as the active material, can provide a hassle-free way to assemble a large micro-LED array and emphasis the full-color demonstration via colloidal quantum dot. These quantum dots can be patterned by porous structure, inkjet, or photo-sensitive resin. In addition to the micro-LED devices, the peripheral components or technologies are equally important. Microchip transfer and repair, heterogeneous integration with the electronics, and the novel 2D material cannot be ignored, or the overall display module will be very power-consuming. The AR is one of the potential customers for micro-LED displays, and the user experience so far is limited due to the lack of a truly qualified display. Our analysis showed the micro-LED is on the way to addressing and solving the current problems, such as high loss optical coupling and narrow field of view. All these efforts are channeled to achieve an efficient display with all ideal qualities that meet our most stringent viewing requirements, and we expect it to become an indispensable part of our daily life.
A Elena Piceno-Martínez et al 2023 J. Phys. Photonics 5 042001
Entanglement and Einstein–Podolsky–Rosen (EPR) steering are nonlocal quantum correlations, which are relevant resources for quantum information protocols. EPR steering, or quantum steering, refers to the correlation where a party might 'steer', or modify, the state of another, which is spatially separated. Entanglement is a symmetric resource while steering is asymmetrical, since it depends on the direction of the effect. Due to these different characteristics and the therefore different possible applications, there has been both theoretical and experimental research on forms to certify the distinct quantum nonlocal correlations. In recent years, alongside the investigation on quantum correlations between two systems, there has been a great interest in investigating multipartite/multimode entanglement as well as steering, since they include a high dimension and it may be possible to store more information than in a single qubit. In this review, we will summarize the different criteria and measures that have been developed for the characterization of these two kinds of correlations. We first focus on bipartite entanglement and steering. We then review the progress that has been made in the investigation of multipartite quantum correlations. We revise the theoretical work in quantum nonlocal correlation witnesses and measures, which respectively allow one to certify that the system is entangled or presents EPR steering, and give a quantification of the content of these correlations in the system. Then, we briefly review the experiments that have been designed and that demonstrate multipartite quantum correlations. We also include applications in quantum information protocols, in particular in quantum teleportation and quantum cryptography.
Mengxin Ren et al 2023 J. Phys. Photonics 5 032501
In nonlinear optical systems, the optical superposition principle breaks down. The system's response (including electric polarization, current density, etc) is not proportional to the stimulus it receives. Over the past half century, nonlinear optics has grown from an individual frequency doubling experiment into a broad academic field. The nonlinear optics has not only brought new physics and phenomena, but also has become an enabling technology for numerous areas that are vital to our lives, such as communications, health, advanced manufacturing, et al. This Roadmap surveys some of the recent emerging fields of the nonlinear optics, with a special attention to studies in China. Each section provides an overview of the current and future challenges within a part of the field, highlighting the most exciting opportunities for future research and developments.
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Cameron et al
Quantum imaging enhances imaging systems performance, potentially surpassing fundamental
limits such as noise and resolution. However, these schemes have limitations and are still a long way
from replacing classical techniques. Therefore, there is a strong focus on improving the practicality
of quantum imaging methods, with the goal of finding real-world applications. With this in mind,
in this tutorial we describe how the concepts of classical light shaping can be applied to imaging
schemes based on entangled photon pairs. We detail two basic experimental configurations in which
a spatial light modulator is used to shape the spatial correlations of a photon pair state and highlight
the key differences between this and classical shaping. We then showcase two recent examples that
expand on these concepts to perform aberration and scattering correction with photon pairs. We
include specific details on the key steps of these experiments, with the goal that this can be used as
a guide for building photon-pair-based imaging and shaping experiments.
Passeri et al
Brillouin spectroscopy has recently attracted attention as a powerful tool for the characterisation of the mechanical properties of heterogeneous materials, particularly in the biological and biomedical domains. This study investigates the procedure to use Brillouin data to provide relevant morphological parameters of micro-structured samples. When acquiring Brillouin spectra at the interface between two regions of the sample, the spectrum shows signatures of both regions. This feature can be used to precisely identify the position of the interfaces by analysing the evolution of the fitting parameters of the Brillouin spectra acquired by performing a linear scan across the interface. This concept has been demonstrated measuring the thickness of adherent HEK 293T cells. The results are validated using fluorescence microscopy, showing an excellent agreement. The present analysis showcases the wealth of information present in the Brillouin spectrum and the potentiality of Brillouin spectroscopy not only for mechanical characterization but also for label-free, high-resolution imaging of sample morphology. The study introduces the possibility of correlating mechanical properties and shape of biological samples using a single technique.
Meulebroeck et al
Given the global rise in antimicrobial resistance levels, an urgent need exists to obtain the Minimal Inhibitory Concentration (MIC) of an antibiotic as early as possible. In this paper we present the first test results of a light-based concept where the interaction of a laser beam with the drug-bacterium sample is used for calculating MIC values within 6 hours after cultivation. For this preliminary study, a total of 163 drug-bacterium pairs were tested and benchmarked with broth microdilution (BMD). The pathogen set included Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, Staphylococcus capitis, Staphylococcus cohnii, Staphylococcus epidermis, Staphylococcus haemolyticus, Enterococcus and Streptococcus pneumoniae. The selected drugs belonged to 10 different classes. The method under investigation showed a categorical concordance of 86.1% and an essential agreement of 80.3% with BMD. Due to its simplicity, the concept can be easily implemented on existing commercial platforms. This research shows a promise for further studies potentially leading to a novel concept that can be employed to rapidly determine MIC values.
Chen et al
In recent years, the field of metal-halide perovskite emitters has rapidly emerged as a new community in solid-state lighting. Their exceptional optoelectronic properties have contributed to the rapid rise in external quantum efficiencies (EQEs) in perovskite light-emitting diodes (PeLEDs) from <1% (in 2014) to approaching 30% (in 2023) across a wide range of wavelengths. However, several challenges still hinder their commercialization, including the relatively low EQEs of blue/white devices, limited EQEs in large-area devices, poor device stability, as well as the toxicity of the easily accessible lead components and the solvents used in the synthesis and processing of PeLEDs. This roadmap addresses the current and future challenges in PeLEDs across fundamental and applied research areas, by sharing the community's perspectives. This work will provide the field with practical guidelines to advance PeLED development and facilitate more rapid commercialization.
Schumacher et al
Lens biomechanical properties are critical for our eyes to accommodate. While it's well understood that lens mechanical properties change with age, different experimental techniques have been used over the years, with varying results on how the lens modulus changes. In this study, we developed a spatial-varying elasticity model to characterize the overall elastic modulus of the lens and establish its effect on accommodation. First, to validate the model, ex vivo porcine lenses underwent compression testing using biopsy punches of different diameter to change the percentage of nucleus within samples. Importantly, we found that, indeed, changing nucleus/cortex spatial ratio produces dramatic (~7-fold) increase in overall sample modulus. Next, in vivo clinical measurements of the spatial-varying lens modulus were used to generate a simplified mechanical-optical model of accommodation. We defined a paraboloid lens with patient-derived modulus and geometry measurements, and a statics simulation and ray tracing analysis was performed through the deformed and undeformed lens. The resulting accommodation estimates agree with general accommodation expectations.