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Dielectric materials that are low‐loss in the visible spectrum provide a promising platform to realize the pragmatic features of metasurfaces. Here, all‐dielectric, highly efficient, spin‐encoded transmission‐type metaholograms (in the visible domain) are demonstrated by utilizing hydrogenated amorphous silicon (a‐Si:H). In comparison to previously reported visible metaholograms based on TiO2 and other dielectric materials, all‐dielectric metasurfaces provide a cost‐effective more straightforwardly fabricated (aspect ratio 4.7), CMOS compatible, and comparably efficient solution in the visible domain. A unique way of utilizing polarization as an extra degree of freedom in the design to implement transmission‐type helicity‐encoded metaholograms is also proposed. The produced images exhibit high fidelity under both right and left circularly polarized illuminations. The proposed cost‐effective and CMOS‐compatible material and methods open up an avenue for on‐chip development of numerous new phenomena with high efficiency in the visible domain.

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We systematically studied the two-body loss in a two-component Fermi gas of 6 Li atoms near a pwave Feshbach resonance. The two-body loss rate constants were measured for various temperatures and magnetic fields using atoms trapped in three-dimensional and quasi-two-dimensional traps. Our results were nicely reproduced by a theoretical model that incorporates the two-body loss as an imaginary part to the inverse of the scattering volume in the scattering amplitude expression. The observed loss suppression in quasi-two-dimensional traps may provide a promising strategy to realize a p-wave superfluid in a system of ultracold atoms.

We selectively create p-wave Feshbach molecules in the m l = ±1 orbital angular momentum projection state of 6 Li. We use an optical lattice potential to restrict the relative momentum of the atoms such that only the m l = ±1 molecular state couples to the atoms at the Feshbach resonance. We observe the hollow-centered dissociation profile, which is a clear indication of the selective creation of p-wave molecules in the m l = ±1 states. We also measure the dissociation energy of the p-wave molecules created in the optical lattice and develop a theoretical formulation to explain the dissociation energy as a function of the magnetic field ramp rate for dissociation. The capability of selecting one of the two closely-residing p-wave Feshbach resonances is useful for the precise characterization of the p-wave Feshbach resonances.

We experimentally confirmed the threshold behavior and scattering length scaling law of the three-body loss coefficients in an ultracold spin-polarized gas of ^{6}Li atoms near a p-wave Feshbach resonance. We measured the three-body loss coefficients as functions of temperature and scattering volume, and we found that the threshold law and the scattering length scaling law hold in limited temperature and magnetic field regions. We also found that the breakdown of the scaling laws is due to the emergence of the effective-range term. This work is an important first step towards a full understanding of the loss of identical fermions with p-wave interactions.

The transformation of a conventional power system to a smart grid has been underway over the last few decades. A smart grid provides opportunities to integrate smart homes with renewable energy resources (RERs). Moreover, it encourages the residential consumers to regulate their home energy consumption in an effective way that suits their lifestyle and it also helps to preserve the environment. Keeping in mind the techno-economic reasons for household energy management, active participation of consumers in grid operations is necessary for peak reduction, valley filling, strategic load conservation, and growth. In this context, this paper presents an efficient home energy management system (HEMS) for consumer appliance scheduling in the presence of an energy storage system and photovoltaic generation with the intention to reduce the energy consumption cost determined by the service provider. To study the benefits of a home-to-grid (H2G) energy exchange in HEMS, photovoltaic generation is stochastically modelled by considering an energy storage system. The prime consideration of this paper is to propose a hybrid optimization approach based on heuristic techniques, grey wolf optimization, and a genetic algorithm termed a hybrid grey wolf genetic algorithm to model HEMS for residential consumers with the objectives to reduce energy consumption cost and the peak-to-average ratio. The effectiveness of the proposed scheme is validated through simulations performed for a residential consumer with several domestic appliances and their scheduling preferences by considering real-time pricing and critical peak-pricing tariff signals. Results related to the reduction in the peak-to-average ratio and energy cost demonstrate that the proposed hybrid optimization technique performs well in comparison with different meta-heuristic techniques available in the literature. The findings of the proposed methodology can further be used to calculate the impact of different demand response signals on the operation and reliability of a power system.

We describe the three-body loss coefficient of identical fermions with p-wave interactions using a set of rate equations in which three-body recombination happens via an indirect process. Our theoretical treatment explains experimental results just above the universal scaling law regime of weak interactions. Furthermore, we theoretically extend and experimentally verify the rate equation model for the case of atoms trapped in two dimensions. Moreover, we find that the three-body loss coefficient in a two-dimensional trap is proportional to A 3 p in the weakly interacting regime, where Ap is the scattering area. Our results are useful in understanding three-body physics with p-wave interactions.