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The international community has committed to achieve 169 Sustainable Development Goal (SDG) targets by 2030 and to enhance climate adaptation under the Paris Agreement. Despite the potential for synergies, aligning SDG and climate adaptation efforts is inhibited by an inadequate understanding of the complex relationship between SDG targets and adaptation to impacts of climate change. Here we propose a framework to conceptualise how ecosystems and socio-economic sectors mediate this relationship, which provides a more nuanced understanding of the impacts of climate change on all 169 SDG targets. Global application of the framework reveals that adaptation of wetlands, rivers, cropland, construction, water, electricity, and housing in the most vulnerable countries is required to safeguard achievement of 68% of SDG targets from near-term climate risk by 2030. We discuss how our framework can help align National Adaptation Plans with SDG targets, thus ensuring that adaptation advances, rather than detracts from, sustainable development.

The emergence of artificial intelligence (AI) and its progressively wider impact on many sectors requires an assessment of its effect on the achievement of the Sustainable Development Goals. Using a consensus-based expert elicitation process, we find that AI can enable the accomplishment of 134 targets across all the goals, but it may also inhibit 59 targets. However, current research foci overlook important aspects. The fast development of AI needs to be supported by the necessary regulatory insight and oversight for AI-based technologies to enable sustainable development. Failure to do so could result in gaps in transparency, safety, and ethical standards., Artificial intelligence (AI) is becoming more and more common in people’s lives. Here, the authors use an expert elicitation method to understand how AI may affect the achievement of the Sustainable Development Goals.

GINGERINO is one of the most sensitive Sagnac laser-gyroscopes based on an heterolithic mechanical structure. It is a prototype for GINGER, the laser gyroscopes array proposed to reconstruct the Earth rotation vector and in this way to measure General Relativity effects. Many factors affect the final sensitivity of laser gyroscopes, in particular, when they are used in long-term measurements, slow varying environmental parameters come into play. To understand the role of different terms allows to design more effective mechanical as well as optical layouts, while a proper model of the dynamics affecting long-term (low frequency) signals would increase the effectiveness of the data analysis for improving the overall sensitivity. In this contribution, we focus our concerns on the effects of room temperature and pressure aiming at further improving mechanical design and long-term stability of the apparatus. Our data are compatible with a local orientation changes of the Gran Sasso site below $$\mu $$ μ rad as predicted by geodetic models. This value is consistent with the requirements for GINGER and the installation of an high-sensitivity Sagnac gyroscope oriented at the maximum signal, i.e. along the Earth rotation axes.

The debate on gravity theories to extend or modify General Relativity is very active today because of the issues related to ultra-violet and infra-red behavior of Einstein's theory. In the first case, we have to address the Quantum Gravity problem. In the latter, dark matter and dark energy, governing the large scale structure and the cosmological evolution, seem to escape from any final fundamental theory and detection. The state of art is that, up to now, no final theory, capable of explaining gravitational interaction at any scale, has been formulated. In this perspective, many research efforts are devoted to test theories of gravity by space-based experiments. Here we propose straightforward tests by the GINGER experiment, which, being Earth based, requires little modeling of external perturbation, allowing a thorough analysis of the systematics, crucial for experiments where sensitivity breakthrough is required. Specifically, we want to show that it is possible to constrain parameters of gravity theories, like scalar-tensor or Horava-Lifshitz gravity, by considering their post-Newtonian limits matched with experimental data. In particular, we use the Lense-Thirring measurements provided by GINGER to find out relations among the parameters of theories and finally compare the results with those provided by LARES and Gravity Probe-B satellites., 15 pages, 3 figures, accepted for publication in EPJP

The occurrence of plasmon resonances on metallic nanometer-scale structures is an intrinsically nanoscale phenomenon, given that the two resonance conditions (i.e., negative dielectric permittivity and large free-space wavelength in comparison with system dimensions) are realized at the same time on the nanoscale. Resonances on surface metallic nanostructures are often experimentally found by probing the structures under investigation with radiation of various frequencies following a trial-and-error method. A general technique for the tuning of these resonances is highly desirable. In this paper we address the issue of the role of local surface patterns in the tuning of these resonances as a function of wavelength and electric field polarization. The effect of nanoscale roughness on the surface plasmon polaritons of randomly patterned gold films is numerically investigated. The field enhancement and relation to specific roughness patterns is analyzed, producing many different realizations of rippled surfaces. We demonstrate that irregular patterns act as metal–dielectric–metal local nanogaps (cavities) for the resonant plasmonic field. In turn, the numerical results are compared to experimental data obtained via aperture scanning near-field optical microscopy.

A study of the phototermal instabilities in a Fabry–Perot cavity is reported, where one mirror consists of a silicon-nitride membrane coated by the molecular organic semiconductor tris(8-hydroxyquinoline) aluminum and silver layers. We propose a theoretical model to describe the back-action associated with the delayed response of the cavity field to the radiation pressure force and the photothermal force. For the case under investigation, the photothermal force response occurs on a timescale that is comparable to that of mirror oscillations and dominates over the radiation pressure force. A phase diagram analysis has been performed to map the stability of the static solution as a function of the control parameters. The model equations are integrated numerically and the time history is compared to experimental measurements of the transmitted field and displacement of the membrane. In both experimental and theoretical data we observe large amplitude oscillations when the cavity length is scanned at a low speed compared to the growth rate of the instability. The perturbation is found to evolve through three regimes: sinusoidal oscillations, double peaks and single peaks followed by a lethargic regime. When the cavity length is scanned in opposite directions, dynamical hysteresis is observed, whose extension has a power law dependence on the scanning rate.

We report the features of an ion source based on two-color photoionization of a laser-cooled cesium beam outsourced from a pyramidal magneto-optical trap. The ion source operates in continuous or pulsed mode. At acceleration voltages below 300 V, it delivers some ten ions per bunch with a relative energy spread Delta U-rms/U similar or equal to 0.032, as measured through the retarding field-energy-analyzer approach. Space-charge effects are negligible thanks to the low ion density attained in the interaction volume. The performances of the ion beam in a configuration using focused laser beams are extrapolated on the basis of the experimental results. Calculations demonstrate that our low-energy and low-current ion beam can be attractive for the development of emerging technologies requiring the delivery of a small amount of charge, down to the single-ion level and its eventual focusing in the 10-nm range.

We have developed an apparatus for nanostructure fabrication based on direct deposition of laser-manipulated cesium vapors onto pyrolitic graphite. Key features of our apparatus are production and manipulation of a longitudinally cooled atom beam, which allows for straightforward operation in the moderate to low flux density conditions. Both unstructured and structured low surface coverage depositions have been carried out and samples carefully analyzed at the atom scale by in situ tunneling microscopy. Results represent a step forward to the realization of a novel technology for space-controlled deposition of few, eventually single, atoms.

A new structure is proposed to improve the external quantum efficiency of porous silicon (PS) light emitting diodes (LED). It is based on a heterojunction between n-type doped silicon and PS. The heterojunction is formed due to the doping selectivity of the etching process used to form PS. The improvement of the proposed LED structure with respect to usual metal/PS LED is demonstrated. This is thought to be due to a different injection mechanism for which carriers are injected directly into conduction band states. Anodic oxidation experiments show further improvements in the LED efficiency.

Transfer of excitation from cadmium to sodium atoms was investigated in anheat pipe oven illuminated by a pulsed laser tuned on the intercombinationtransition of cadmium. A rich emission spectrum with cadmium as well assodium lines was observed. Intramultiplet mixing distributes the initialexcited level population 5p3P1 to the nearby fine structurelevels 5p3P0,2 of the same multiplet. We have experimentalevidence that the energy transfer pathway is from Cd (5p3PJ) to Na(4p2PJ) which is collisionally rapidly converted toNa(3d2DJ), from which the strongest emission was observed.PACS No.: 34.90+q

We present an in situ diagnostics for time- and space-resolved analysis of atomic oxygen during pulsed laser ablation in the presence of a molecular oxygen environment. Our diagnostics are based on transient atomic absorption spectroscopy and exploits diode laser as the probe source. The results. acquired during ablation of YBCO and NiTi targets, demonstrate the sensitivity of the technique in detecting the atomic oxygen produced through dissociation of O 2 environment gas, and show the formation of a relatively large density of atomic oxygen close to the plume range in the experimental conditions typical for deposition of superconductive thin films.

We have deposited by pulsed laser ablation YBCO/YSZ bilayers on flexible Ni-based (Inco alloy C-276) substrates. As confirmed by X-ray diffraction spectra, the YBCO film grows mainly along thec-axis direction. However, a mosaic spread of 10 degrees, evaluated from the (005) YBCO pole figure, and the results of a film texture analysis indicate that more effort is required to obtain a completec-axis orientation along with in-plane alignment for the YBCO layer.

We currently use optical spectroscopy as an in-situ diagnostic tool in the pulsed laser ablation and deposition of superconductive and ferroelectric thin films. The emission from the ablated species is collected from both directions normal and parallel to the plume expansion axis. Space and time resolved measurements enable a quantitative evaluation of density and temperature of the plasma produced by the laser-plume interaction. This characterization of the plume in the early stages of its expansion is important to understand the mechanisms responsible for the efficient laser-matter energy coupling typical of the pulsed laser ablation and deposition process.

Optical measurements have been performed on pulsed laser ablation of ceramic (YBCO and PZT) and metal (Al and Ti) targets at a pulsed laser fluence in the range of 0.06–3.6 J cm−2. Time resolved target reflectivity measurements demonstrate the formation of a plasma layer able to absorb the laser radiation above the target surface. Plume optical emission measurements, collected both from the parallel and the normal directions to the plume expansion axis, enable an evaluation of the plasma temperature and density as a function of the time after the arrival of the laser pulse.

We report the observation at thermal energies of the energy pooling collisions 6P + 6P in Cs vapour excited by a laser diode. The rate coefficients of the process Cs(6P3/2) + Cs(6P3/2) → Cs(7P3/2, 1/2) + Cs(6S1/2) are measured for the first time.

Time‐of‐flight mass spectrometry and covariance mapping technique were used to investigate the formation of charged species in the laser ablation of a Pb(Ti0.48Zr0.52)O3 target. Mass spectra were taken both in high vacuum and in an oxygen environment in order to clarify the effect of oxygen on the plume composition. The analysis of charged species in the plume has been carried out as a function of the distance between the target and spectrometer axis. The relative abundance of atomic, monoxide, and heavy ions has been measured and discussed. The velocities of atomic ions in the laser plume have been evaluated. Pb transport from target to substrate has been found to be mainly due to Pb‐containing heavy species, whose abundance is greater in an oxygen environment with respect to a high vacuum condition. Ionic yield and covariance mapping analysis indicate that oxidation of ablated material starts at a distance very close to the plume range. The data show that, close to the deposition distance, a significant fraction of the plume is composed of heavy species containing Pb and oxides. These are appropriate precursors for the stoichiometric growth of ferroelectric films. The oxides are important carriers of oxygen atoms, and the Pb‐containing heavy species preserve the metal stoichiometry with respect to Pb, which is the most volatile element in the composition.

We present simulations of bound–bound and bound–free emissions of the NaCd* excimer, along with new experimental results concerning the red band system. The simulations, based on ab initio potential energy curves, confirm that the initial states are 2 2Σ+ for the red emission and 2 2Π for the blue emission of NaCd*. The two main peaks in the blue band system are due to spin–orbit splitting. The band shape obtained in the simulations is extremely variable, depending on the population distribution of the vibrational states of NaCd*. The comparison of simulated and measured spectra leads us to conclude that, in the experimental conditions adopted here and in previous work, the thermal equilibration of the excimer is far from complete.

The time‐of‐flight mass spectrometry has been used to investigate the formation of charged species in the laser ablation of YBa2Cu3O7−δ (YBCO) target. Mass spectra were taken both in high vacuum and in oxygen environment for two values of the laser energy density (0.74 and 2.5 J cm−2). The analysis of the charged species in the plume has been carried out as a function of the distance between the target and the spectrometer axis and the relative abundance of Cu, Y, Ba, CuO, YO, and BaO ions has been measured and discussed. In this paper the formation of heavy species and YBCO clusters is also discussed. The plume range has been evaluated as a function of the absorbed energy at a distance from the target plane close to that one at which good quality high Tc superconducting films are obtained, the plume composition has been found to be characterized by the presence of a series of oxide clusters originating from the interaction between the ablated material and the environmental oxygen. This confirms that the interaction between the plume and the environmental oxygen plays an important role both in the formation of heavy charged species and in the capture of the oxygen required to obtain the correct stoichiometric composition of the deposited film.

We have used a Raman microprobe technique for the characterisation and the diagnostic of YBCO superconducting thin films deposited by Pulsed-Laser Ablation (PLA) on MgO insulating substrates. Using polarisation analysis associated with sample rotations we developed a method for films orientation determination without any request for absolute calibration of the Raman spectra. The use of a bidimensional multichannel detector (OMA 4) allowed an overall detection time of 40 minutes. Each spectrum (shift range from 100 cm−1 to 700 cm−1) takes about 600 seconds. The results of this detection were used to determine the oxygen content, from the position of the Raman mode at 500 cm−1 Homogeneity was checked with the spatial resolution allowed by the dimension of the focused laser beam (10 μm).

We report the observation of reactive collisions involving laser excited metastable 5p 3 P 1 Cd atoms and ground state Na 2 molecules. As result of these collisions the NaCd intermetallic excimer is formed in a bound excited electronic state and its typical bound-free emission to the ground state is detected. Experimental comparison of this new collision channel with the photochemical production of NaCd in collisions between electronically excited Na 2 and ground state Cd atoms is presented.

We report the first evidence for the production of the electronically excited NaCd excimer following resonant excitation of the metastable Cd(5p 3P1) state. Dependence of intensity of emission from NaCd upon buffer gas pressure, temperature, and exciting laser wavelength is discussed and possible production mechanisms are proposed.

Near-field optical spectroscopy has been used to investigate photoluminescence features of porous silicon microcavity samples with a subwavelength space resolution. The emission is found to be markedly dependent on the lateral position, with the presence of relatively narrow spectral features peaked at different wavelengths in the range 610–690 nm. Furthermore, the spectrum obtained by summing up spectra taken at different sampling points (relative displacement ∼100 nm) recovers the standard (macroscopic) photoluminescence spectrum of porous silicon, except for the presence of a dip around the resonance wavelength of the microcavity resonator.

The technique of covariance mapping has been applied to time-of-flight spectroscopy of laser ablated ions from YBCO. The spatial analysis of the plume has been performed. In the geometry in which superconductive films are obtained we found a modulation of the ion cluster signal corresponding to an oxygen atom capture.

Pb(Ti0.48Zr0.52)O3 films produced by pulsed laser ablation deposition have been locally examined for their homogeneity and thickness through a comparative use of Raman and infrared spectroscopy. Raman scattering intensity appears to be an oscillating function of the position of the point under measurements. The observed oscillations were explained by light interference effects in the film and used to obtain the thickness profile and the refractive index dispersion of the film. The intensity distribution in Raman spectra across the film differs from that of the target. This difference is larger at the center than near the edge of the film.

Short-length prototypes of coated conductors consisting of YBa2Cu3O7−x/yttrium-stabilized zirconia (YBCO/YSZ) bilayers have been fabricated by pulsed laser deposition (PLD) onto biaxially textured NiFe substrates. Scanning probe microscopy has been used for a detailed investigation of local sample properties. In particular, near-field scanning optical microscopy has been exploited to reconstruct a high resolution map of the surface optical scattering properties, which can be related to fluctuations of oxygen stoichiometry at the grain space scale.

We have coated, by laser deposited NiTi films, Si-based cantilevers, of the kind commercially available as atomic force microscopy probes. The samples exhibited peculiar mechanical features ascribed to combination of shape-memory and bimetal effects. Our findings demonstrate the capabilities of laser deposition in fabricating metal alloys, and, at the same time, open the way to a simple process for the fabrication of basic components in microelectromechanical systems.

Near-field optical spectroscopy has been used to study the photoluminescence features of a porous silicon device at room temperature, with a subwavelength space resolution of about 50-100nm. In particular, a prototype of a porous silicon-based light-emitting diode has been characterized by imaging morphology, near-field scattering intensity and emission maps of the same portion of the sample with a space resolution of better than 60 nm. Structured emitting centres are found on the porous regions with size ranging from 200 nm to 1 μm. Emission features, acquired as near-field spectra as well as emission maps at fixed wavelengths, provide crucial information on the prototype structure at the nanometric level, exploitable for improvement in production steps as well as for the study of the dominant working mechanisms of the device.

We carry out photoionization experiments on laser-cooled alkali atoms by irradiating rubidium and cesium magneto-optical traps (MOTs) with a photoionizing laser beam. Analysis of the loading behavior of the traps allows us to determine photoionization cross-sections for the first excited state of rubidium and cesium based on a trap load/loss model. In addition, our experimental findings reveal systematic peculiarities, which can be ascribed to the low temperature of the atomic samples under investigation.

Excitons localized at compositional potential fluctuations are individually resolved by spatially resolved near-field luminescence in ZnCdSe/ZnSe quantum wells at room temperature. Localization is found to occur on a scale length of about 100 nm, in Cd-rich clusters in which the local Cd content varies by approximately 1% with respect to the nominal composition, and in steps of about 0.3%. A microscopic modeling of the localized exciton states is presented, which describes quite well the observed near-field spectra.

The dielectric constant and the reflectivity spectrum of polycrystalline RuO2 films, grown by pulsed laser deposition, are presented as deduced by optical reflection and electron energy-loss spectroscopy. The similarities of these spectra with those obtained on single crystals, suggest that the production of RuO2 by laser ablation is a very good tool in obtaining films with electronic and structural characteristics equivalent to those of the bulk material.

We report the observation of strong red- and blue-light emission in free-standing porous-silicon samples prepared from n + substrates at different anodization current densities. The surface morphology of the free-standing samples has been analyzed by means of atomic-force microscopy. Upon excitation with nanosecond pulses at room temperature, both blue and red luminescence bands appear, peaked around 3.2 and 2.0 eV, respectively. An extensive study of the time-resolved behavior of the photoluminescence signal reveals different dynamical features for the two spectral regions. The observed long decay time (several μs) of the red band reflects the predominant effect of non-radiative processes and is consistent with models based on excition diffusion through the interconnected silicon nanocrystals (quantum dots) skeleton. The relatively fast blue-band decay time (≈400 ns) is shown to be related to non-radiative recombination through trap states at the silicon nanocrystal surface.

Time of flight mass spectrometry and covariance mapping technique have been used to investigate the formation of charged species in the laser ablation of Pb(Ti 0.48 Zr 0.52 )O 3 (PZT) targets. The mass spectral analysis has been carried out as a function of distance h from the target, both in high vacuum condition (10 −7 mbar) and in oxygen environment (0.2 mbar background pressure). The relative abundance of atomic, monoxide and heavy ions has been measured and discussed. In high vacuum condition the relative abundance of heavy ions is a decreasing function of the distance from the target and becomes very low, about 8%, at the deposition distances. On the contrary, the relative abundance of monatomic ions and simple oxides increases with the distance from the target. In oxygen environment the relative abundance of heavy ions does not show a monotonic trend. This is likely due to the contemporary presence of fragmentation and aggregation processes. However, at the deposition distance a significant part of the plume, about 40%, is composed of large aggregates containing Pb. Moreover, the covariance mapping analysis shows that the light species are mainly produced by dissociation of the heavy aggregates.

We report for the first time the production of the LiHg excimer by a photochemical reaction of excited Li2 molecules with Hg(6s2 1S0). Excitation energy was provided by a cw ultraviolet (UV)‐argon ion laser operating in single‐line and in multi‐line mode or by pulsed XeCl excimer laser at 3080 A. We observed bound‐free emission of LiHg in the form of diffuse bands peaking at 4450 and at 4670 A. The latter was structured by bound–bound emission lines. Relativistic ab initio calculations for the potential energy curves of LiHg and for the relevant dipole transition moments were performed. Using these results, an interpretation of the observed emission is presented.

Diagnostics of pulsed laser ablation and deposition of superconductive YBCO (YBa2Cu3O7−x) and ferroelectric PZT (PbZrxTi1−xO3) thin films has been accomplished by measuring the Stark broadening of the laser produced plume. Fluorescence emission has been collected from regions along the axis of the plume at different distances from the target surface. The line shape of some selected transitions has been analyzed and the electron density ne determined from the observed linewidth. The measured values of ne are in the range 0.4–30×1017 cm−3 for YBCO and 0.1–6×1017 cm−3 for PZT. A scaling law of ne as a function of the distance from the target has been found, which indicates a one‐dimensional behavior in the early stage of the electron cloud expansion. The dependence of ne on the presence of the ambient oxygen gas and on the laser fluence has been also investigated. The results of the diagnostics are compared with theoretical predictions and correlated with the deposition parameters.

Photoassisted processes in C60/O2 mixtures unpair spins which delocalize themselves in a symmetric environment. A partial spin-pairing occurs at the calorimetric onset of a reversible, structural transition in the mixture where mass spectroscopy evidences remarkable amounts of oxygen weakly bound to the fullerence lattice. The hypothesis that the paramagnetic species is the cation C60+ is discussed.

I–V DC characteristics have been measured on metal/ porous-silicon structures. In particular, the measurements on metal/ free-standing porous-silicon film/metal devices confirmed the result, already obtained, that the metal/poroussilicon interface plays a crucial role in the transport of any device. Four-contacts measurements on free-standing layers showed that the current linearly depends on the voltage and that the conduction process is thermally activated, the activtion energy depending on the porous silicon film production parameters. Finally, annealing experiments performed in order to improve the conduction of rectifiyng contacts, are described.