Disordered optical metasurfaces: basics, properties, and applications

We demonstrate a hybrid integrated photonic-plasmonic platform in which photonic guided modes are used to efficiently excite localized surface plasmon resonanc e (LSPR) modes of plasmonic nanoresona tors. Efficient coupling of light to the LSPR modes of plasmonic nanoresonators is demonstrated by tight integration of plasmonic nanoresonators on silicon nitride (SiN) microresonators. It is shown that by integrating gold nanoparticles with SiN microresonators, we can achieve high coupling efficiencies (>35%), resulting in large field enhancements. We will discuss the design, fabrication, and characterization of the hybrid platform which consists of gold nanoparticles integrated with SiN microring resonators. Keywords: Plasmonics, Integrated optics, Microresonators 1. INTRODUCTION Plasmonic nanoresonators show localized surface plasmon resonance (LSPR) modes. These resonances have very small mode volumes and can localize light beyond diffraction limit and they provide ultrahigh field enhancements that can be used in a variety of applications rangi ng from surface enhanced Raman spectroscop y (SERS) [1] to no nlinear optics [2]. Plasmonic nanoresonators are made in different shapes such as nanodisks [3], nanorods[4] , bowties [5], and nanoshells [6] and from different materials such as gold and silver. By changing the size and shape of the plasmonic nanoparticles LSPR modes can be tuned from visible to infrared range of the spectrum and different levels of field enhancements can be achieved. Plasmonic nanoparticles are e ither fabricated using top down fabrication techniques or they are chemically synthesized [7]. The LSPR modes of these plasmonic nanoparticles are usually excited using free space optics by focusing light using a lens on the nanoparticles either dispersed in a solution or immobilized on a substrate. In practice, many of these nanoparticles are interrogated to obtain an appreciable level of signal to be detected. The ability to efficiently couple light to individual plasmonic nanoresonators is necessary to realize practical devices. Also, it makes the study of resonance behavior of plasmonic nanoresonators possible without the interference effect of a collection of these nanoresonators. There have been some efforts to characterize the resonance behavior of single plasmonic nanoresonators [8, 9]. The coupling of light to the LSPR mode of single nanoresonators is not usually efficient and only a small portion of the incident power is coupled to the LSPR modes. For example a gold nanorod with an aspect ratio of 3.9 and an effective radius of r

From smart energy community to smart energy municipalities: Literature review, agendas and pathways

Metasurface is a class of two-dimensional microstructure functional materials, which has an ability of modulating light in subwavelength region and becomes a hot topic during the last decade. An advantage of metasurfaces is their versatility by invoking the degrees of freedom of light field to achieve various functionalities. In this paper, we report methods of using the polarization and dispersion of light to achieve multifunctional metasurface devices, allowing the different degrees of freedom of light to carry independent phase profiles to achieve the polarization-dependent conversion of Bessel beams with different orders and numerical apertures as well as integrated optical tweezers-optical spanner metasurface. Also, the wavelength-controlled multifunctional metalens by introducing an improved genetic algorithm has been implemented. We envision our research are expected to be the potential candidates in multifunctional integrated optical devices.

Renewable energy systems have emerged as a crucial research area due to the escalating demand for sustainable energy solutions. With the advancement of renewable energy, the electric-thermal coupling within multi-energy systems has become more intricate. Bi-directional electric-thermal storage and conversion technologies have emerged as a potential solution to address the challenges associated with efficient energy utilization. This paper focuses on the joint planning and operation optimization of renewable energy systems considering bi-directional electric-thermal storage and conversion. The integrated framework for renewable energy systems incorporating a bi-directional electric-thermal storage and conversion unit is designed, and the joint planning and operation optimization method is proposed. Case studies are conducted based on typical annual energy demand and solar radiation characteristics in Beijing, China. Numerical results show that the proposed method can effectively handle the coupling and bi-directional conversion characteristics of electrical and thermal energy, achieving energy cost savings while fulfilling the energy demands of the system. The proposed system has a capital expenditure of USD 261,251.4 and an operating expenditure of USD 177,007.1, which shows a total cost reduction of 12.28% compared to the lithium-ion battery system, providing better economic performance while further enhancing the flexibility of energy utilization. These research findings contribute to the development of more efficient and sustainable renewable energy systems, providing a valuable reference for future research and practical applications within the energy field.

Two-dimensional Pd-Cellulose with optimized morphology for the effective solar to steam generation

Climate change has become a global issue and is predicted to impact less-developed regions, such as sub-Saharan Africa, severely. Innovative, sustainable renewable energy systems are essential to mitigate climate change’s effects and unlock the region’s potential, especially with the increasing energy demands and population growth. The region relies heavily on fossil fuels, which calls for urgent action towards energy security and expansion. Hybrid floating solar photovoltaic-hydropower (FPV-HEP) technology has emerged as a cost-effective and transformative solution to accelerate the low-carbon energy transition in sub-Saharan Africa. The technology combines solar panels with existing hydropower infrastructure, ensuring energy security while reducing carbon emissions. This technology offers several benefits over conventional ground-mounted solar systems, including efficient land utilization, energy generation, and water conservation. However, its adoption remains challenging due to technical complexities and evolving regulatory frameworks. Despite these challenges, Nigerian energy professionals have preferred renewable alternatives, mainly distributed solar PV and FPV-HEP plants. This collective embrace of FPV and renewables reflects a growing understanding of their critical role in mitigating climate change through sustainable energy practices. This research aims to contribute to the existing body of knowledge and assist policymakers in making informed decisions on adopting this technology. It also stimulates further research on this topic, offering a new potential solution to the ever-increasing demand for green energy in the region to meet their sustainable development needs.

Biomass and bio-energy utilisation in a farm-based combined heat and power facility

The purpose of this study is to make a technological and financial forecast for the future construction of similar facilities based on feasibility data from the Istanbul Domestic Waste Incineration and Energy Production Facility, which was constructed to minimize environmental damage and give domestic solid wastes economic value, as opposed to storing and disposing of them. The study examined the initial investment and operating costs of the facility, the repayment time and profitability calculations, the financial and economic profitability of the project, and the cost and internal profitability rates for other waste disposal facilities to be established, in addition to comparisons with conventional waste management systems (storage or composting) and incineration techniques. By separating themselves as much as possible from conventional waste management systems, systems employing technological methods will be more realistic and cost-effective, both financially and in terms of the environment. To meet rising energy demands and lessen reliance on foreign sources, investments in sustainable renewable energy systems other than fossil fuels must be increased now. It is crucial to accelerate and support investments in environmentally friendly energy technologies through their development. This is the first study conducted in Turkey on obtaining energy by burning domestic solid waste as opposed to storing it.

The global economy is experiencing significant business growth leading to increasing demands for energy. Global energy consumption increased by 2.1 percent in 2017, and according to the 2019 U.S. Energy Information Administration (EIA) reports, the expected energy growth in Asia will reach 50 percent by 2050. Since it is unlikely that these demands will be met using conventional energy systems, the world is moving toward sustainable renewable energy systems (RESs) that are supported by cyberphysical technologies. Additionally, climate change is putting more pressure on governments to reduce their dependency on conventional energy resources and invest more in sustainable renewable energies. The shift from conventional energy sources to renewables is clear, as revealed in 2018 where 30 percent of the U.K. gross electricity consumption was generated by RES (according to the Green Match report on Renewable Energy in the United Kingdom). This transformation has led to the emergence of prosumers (i.e., producers and consumers) capable of both generating and consuming energy. Many households and buildings are now equipped with solar panels that can contribute to the overall energy needs. Power systems need to adapt to renewable energy to provide more efficient and sustainable operations. As such, the concept of smart grid needs to be promoted and looked at more closely in the research and development fields to support such sustainable power systems and energy solutions.

Does the need for economic growth influence energy consumption and CO2 emissions in Nigeria? Evidence from the innovation accounting test

A sustainable-energy policy requires the development of economical and sustainable renewable energy systems. This research focuses on the feasibility of developing a sustainable resource supply chain plan, by using available biomass as a resource for producing electricity in the Loei province, Thailand. A mathematical model has been proposed to determine suitable locations for the biomass power plants, the optimal biomass production, and supplier allocation that result in the lowest operating cost to meet the electricity demand. The availability of different types of biomass, different modes of transportation, and electricity consumption in the Loei province is used to develop the optimisation model. An extended model is also proposed to deal with the perishability of biomass. The proposed models can be used and applied by decision makers to perform different types of analysis in order to assist decision making on the location of biomass plants as well as in the distribution plan.

Debating the sustainability of solar energy: Examining resource construction processes for local photovoltaic projects in France

This research discusses the utilisation of solar power plants (PLTS) in supporting salt production through a hybrid system with PLN electricity. The main objective is to design and optimise an efficient and sustainable renewable energy system, especially in remote areas with limited electricity supply and to determine the needs of PLN electricity and solar panel energy systems during the salt cooking process. This research method collects data by measuring various important components, such as the voltage from the inverter to the stove supplied from PLN electricity and solar panels to the battery. The test results show that salt production requires 700 watts of power from PLN for 1.5 hours with an average voltage of 195-196 volts and a current of 3.3-4 amperes. The voltage of the solar panel to the battery stabilised at 12.58 volts during sunny weather and decreased to 12.21 volts during cloudy weather. This research shows that the solar power plant for salt production has worked effectively. By building a hybrid system of PLN and solar panels to ensure the sustainability of salt production, especially in overcoming the instability of the power generated by solar panels due to weather changes

Optical metasurfaces, capable of manipulating the properties of light with a thickness at the subwavelength scale, have been the subject of extensive investigation in recent decades. This research has been mainly driven by their potential to overcome the limitations of traditional, bulky optical devices. However, most existing optical metasurfaces are confined to planar and rigid designs, functions, and technologies, which greatly impede their evolution toward practical applications that often involve complex surfaces. The disconnect between two-dimensional (2D) planar structures and three-dimensional (3D) curved surfaces is becoming increasingly pronounced. In the past two decades, the emergence of flexible electronics has ushered in an emerging era for metasurfaces. This review delves into this cutting-edge field, with a focus on both flexible and conformal design and fabrication techniques. Initially, we reflect on the milestones and trajectories in modern research of optical metasurfaces, complemented by a brief overview of their theoretical underpinnings and primary classifications. We then showcase four advanced applications of optical metasurfaces, emphasizing their promising prospects and relevance in areas such as imaging, biosensing, cloaking, and multifunctionality. Subsequently, we explore three key trends in optical metasurfaces, including mechanically reconfigurable metasurfaces, digitally controlled metasurfaces, and conformal metasurfaces. Finally, we summarize our insights on the ongoing challenges and opportunities in this field.

Optical metasurfaces (OMs) have emerged as promising candidates to solve the bottleneck of bulky optical elements. OMs offer a fundamentally new method of light manipulation based on scattering from resonant nanostructures rather than conventional refraction and propagation, thus offering efficient phase, polarization, and emission control. This perspective highlights state of the art OMs and provides a roadmap for future applications, including active generation, manipulation and detection of light for quantum technologies, holography and sensing.