Enhancement of optical response with high-index dielectric nanoparticles is attributed to the excitation of their Mie-type magnetic and electric resonances. Here we study Raman scattering from crystalline silicon nanoparticles and reveal that magnetic dipole modes have much stronger effect on the scattering than electric modes of the same order. We demonstrate experimentally a 140−fold enhancement of Raman signal from individual silicon spherical nanoparticles at the magnetic dipole resonance. Our results confirm the importance of the optically-induced magnetic response of subwavelength dielectric nanoparticles for enhancing light-matter interactions.

We propose a novel photothermal approach based on resonant dielectric nanoparticles, which possess imaginary part of permittivity significantly smaller as compared to metal ones. We show both experimentally and theoretically that a spherical silicon nanoparticle with a magnetic quadrupolar Mie resonance converts light to heat up to 4 times more effectively than similar spherical gold nanoparticle at the same heating conditions. We observe photoinduced temperature raise up to 900 K with the silicon nanoparticle on a glass substrate at moderate intensities (<2 mW/μm) and typical laser wavelength (633 nm). The advantage of using crystalline silicon is the simplicity of local temperature control by means of Raman spectroscopy working in a broad range of temperatures, that is, up to the melting point of silicon (1690 K) with submicrometer spatial resolution. Our CMOS-compatible heater-thermometer nanoplatform paves the way to novel nonplasmonic photothermal applications, extending the temperature range and simplifying the thermoimaging procedure.

Abstract-Software development companies are increasingly aiming to become data-driven by trying to continuously experiment with the products used by their customers. Although familiar with the competitive edge that the A/B testing technology delivers, they seldom succeed in evolving and adopting the methodology. In this paper, and based on an exhaustive and collaborative case study research in a large software-intense company with highly developed experimentation culture, we present the evolution process of moving from ad-hoc customer data analysis towards continuous controlled experimentation at scale. Our main contribution is the "Experimentation Evolution Model" in which we detail three phases of evolution: technical, organizational and business evolution. With our contribution, we aim to provide guidance to practitioners on how to develop and scale continuous experimentation in software organizations with the purpose of becoming data-driven at scale. A/B

The concept of high refractive index subwavelength dielectric nanoresonators, supporting electric and magnetic optical resonances, is a promising platform for waveguiding, sensing, and nonlinear nanophotonic devices. However, high concentration of defects in the nanoresonators diminishes their resonant properties, which are crucially dependent on their internal losses. Therefore, it seems to be inevitable to use initially crystalline materials for fabrication of the nanoresonators. Here, we show that the fabrication of crystalline (low-loss) resonant silicon nanoparticles by femtosecond laser ablation of amorphous (high-loss) silicon thin films is possible. We apply two conceptually different approaches: recently proposed laser-induced transfer and a novel laser writing technique for largescale fabrication of the crystalline nanoparticles. The crystallinity of the fabricated nanoparticles is proven by Raman spectroscopy and electron transmission microscopy, whereas optical resonant properties of the nanoparticles are studied using dark-field optical spectroscopy and full-wave electromagnetic simulations.

Optical surface waves, highly localized modes bound to the surface of media, enable manipulation of light at nanoscale, thus impacting a wide range of areas in nanoscience. By applying metamaterials, artificially designed optical materials, as contacting media at the interface, we can significantly ameliorate surface wave propagation and even generate new types of waves. Here, we demonstrate that high aspect ratio (1 to 20) grating structures with plasmonic lamellas in deep nanoscale trenches, whose pitch is 1/10 -1/35 of a wavelength, function as a versatile platform supporting both surface and volume infrared waves. The surface waves exhibit a unique combination of properties, such as directionality, broadband existence (from 4 µm to at least 14 μm and beyond) and high localization, making them an attractive tool for effective control of light in an extended range of infrared frequencies. Main text 2Optical surface waves (SWs) arise at the interface of two dissimilar media with different types of permittivity or permeability 1 . Research on SWs has intensified in the last decade due to their unique properties of surface sensitivity, field localization, unusual dispersion and polarization properties at the nanoscale, stimulating the development of surface photonics 2 . The most studied SWs are surface plasmon-polaritons supported at the interfaces between metals and dielectrics 3 , which enable effective nanophotonic devices for sensing 4 , nano-guiding 5 , and imaging 6 based on near-field techniques. A newly emerging alternative is Dyakonov surface waves existing at the interfaces between anisotropic and isotropic dielectrics 7-10 . Up to present, various types of SWs have mostly been investigated individually. However, we can obtain new features by combining traits from various types of surface waves. This is where metamaterials, an artificially engineered materials and structures 11-13 , can play an essential role because in order to combine different SWs unprecedented and extreme optical parameters are often required. One example of such combined SWs on metamaterial structures are Dyakonov plasmons (DPs) 14,15 , a combination of surface plasmons and Dyakonov waves supported at the boundaries of hyperbolic metamaterials (HMMs) 16 . The diagonal components of the HMMs' permittivity tensors are of different signs, giving rise to hyperbolic iso-frequency contours in the k (wavevector) space accompanied by singularities in the density of optical states in an ideal lossless case. Natural material equivalents of HMMs are often referred to as indefinite media 17,18 . Characteristically, HMMs and their two-dimensional analogues of metasurfaces possess a unique combination of properties including unusually high wavevectors, optical density of states, and anisotropy. These feature lead to a wide variety of HMM potential applications such as broadband enhancement in the spontaneous emission for a single photon source 19,20 , sub-wavelength imaging 21 , sensing 22,23 , thermal engineering 19,20,24 , and steering of opti...