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Abstract Finding suitable p-type dopants, as well as reliable doping and characterization methods for the emerging wide bandgap semiconductor $$\beta$$ β - $${\mathrm{Ga}_{2}\mathrm{O}_{3}}$$ Ga 2 O 3 could strongly influence and contribute to the development of the next generation of power electronics. In this work, we combine easily accessible ion implantation, diffusion and nuclear transmutation methods to properly incorporate the Cd dopant into the $$\beta$$ β - $${\mathrm{Ga}_{2}\mathrm{O}_{3}}$$ Ga 2 O 3 lattice, being subsequently characterized at the atomic scale with the Perturbed Angular Correlation (PAC) technique and Density Functional Theory (DFT) simulations. The acceptor character of Cd in $$\beta$$ β - $${\mathrm{Ga}_{2}\mathrm{O}_{3}}$$ Ga 2 O 3 is demonstrated, with Cd sitting in the octahedral Ga site having a negative charge state, showing no evidence of polaron deformations nor extra point defects nearby. The possibility to determine the charge state of Cd will allow assessing the doping type, in particular proving p-type character, without the need for ohmic contacts. Furthermore, a possible approach for contactless charge mobility studies is demonstrated, revealing thermally activated free electrons for temperatures above $$\sim$$ ∼ 648 K with an activation energy of 0.54(1) and local electron transport dominated by a tunneling process between defect levels and the Cd probes at lower temperatures.

Local distortions in perovskite-like orthochromites are of extreme importance for the properties they exhibit. Here, we present the results of structural and DC magnetisation measurements combined with local probe studies in polycrystalline ErCrO3. The electric field gradient (EFG) parameters’ evolution with temperature shows two clear signals of local environment changes, one at the ferroelectric phase transition (TFE) and the other below 250 K. At the claimed TFE, the EFG changed from a slightly distorted axial symmetric to an EFG with axial symmetry (evidence that the local point-symmetry of the crystal might have changed). At a temperature around 250 K, we observed the development of a magnetic hyperfine field (MHF) and a change in the EFG to an axial slightly distorted one. These observations are rather in line with our magnetisation measurements, as a relatively strong coercive field was observed well above the Cr sub-lattice ordering temperature.

Highly ordered anodic hafnium oxide (AHO) nanoporous or nanotubes were synthesized by electrochemical anodization of Hf foils. The growth of self-ordered AHO was investigated by optimizing a key electrochemical anodization parameter, the solvent-based electrolyte using: Ethylene glycol, dimethyl sulfoxide, formamide and N-methylformamide organic solvents. The electrolyte solvent is here shown to highly affect the morphological properties of the AHO, namely the self-ordering, growth rate and length. As a result, AHO nanoporous and nanotubes arrays were obtained, as well as other different shapes and morphologies, such as nanoneedles, nanoflakes and nanowires-agglomerations. The intrinsic chemical-physical properties of the electrolyte solvents (solvent type, dielectric constant and viscosity) are at the base of the properties that mainly affect the AHO morphology shape, growth rate, final thickness and porosity, for the same anodization voltage and time. We found that the interplay between the dielectric and viscosity constants of the solvent electrolyte is able to tailor the anodic oxide growth from continuous-to-nanoporous-to-nanotubes.

Recent developments have led to an enormous increase of publicly available large genomic data, including complete genomes. The 1000 Genomes Project was a major contributor, releasing the results of sequencing a large number of individual genomes, and allowing for a myriad of large scale studies on human genetic variation. However, the tools currently available are insufficient when the goal concerns some analyses of data sets encompassing more than hundreds of base pairs and when considering haplotype sequences of single nucleotide polymorphisms (SNPs). Here, we present a new and potent tool to deal with large data sets allowing the computation of a variety of summary statistics of population genetic data, increasing the speed of data analysis.