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The Ge–In–Se thin films were prepared in high optical qualityviaspin-coating and their surface was patterned using electron beam lithography and optical holography. 

Fabry disease (FD) is a rare disorder resulting from a genetic mutation characterized by the accumulation of sphingolipids in various cells throughout the human body, leading to progressive and irreversible organ damage, particularly in males. Genetically-determined deficiency or reduced activity of the enzyme (alpha – Galactosidase; α-Gal) leads to the accumulation of sphingolipids in the lysosomes of various cell types, including the heart, kidneys, skin, eyes, central nervous system, and digestive system, triggering damage, leading to the failure of vital organs, and resulting in progressive disability and premature death. FD diagnostics currently depend on costly and time-intensive genetic tests and enzymatic analysis, often leading to delayed or inaccurate diagnoses, which contribute to rapid disease progression. In this research, midinfrared Fiber Evanescent Wave Spectroscopy (FEWS) supported by statistical analysis and Machine Learning (ML) algorithms is shown to be an innovative and reliable method to detect globotriaosylsphingosine (Lyso-Gb3) FD biomarker in urine and serum samples by monitoring infrared spectra alone. ML showed a high selectivity for FD in the spectral range of Amide A and Amide I in blood serum, and α-D-galactosyl residues of glycosphingolipids in urine. The developed approach offers a promising, cost-effective express diagnostic tool sensitive enough for early FD detection and monitoring. 

The influence of Bi on the structure and physical properties of Ge2Se3-based equichalcogenide glasses and thin films is studied. Thermal analysis shows increased crystallization ability for Bi-modified glasses. Direct current (DC) and alternating current (AC) electrical conductivity for bulk glasses and thin films is investigated in a broad range of temperatures and frequencies, showing a strong dependence on the presence of Bi modifiers. Exposure wavelength dependence of photocurrent is studied at different temperatures for the visible range of spectrum, and correlated with the existence of localized states in the mobility gap of these amorphous semiconductors. Structural peculiarities of the obtained thin films and bulk samples are assessed from X-ray diffraction (XRD) and high-resolution X-ray photoelectron spectroscopy (XPS) measurements. Optical, electrical, and thermal properties are shown to be suitable for various applications in photonics, electronics, and sensor systems. 

We report on the substantial influence of methanol presence on the dissolution mechanism of Ge20Sb5S75 bulk glass with subsequent superior properties of thin films deposited from such solutions. Raman spectroscopy confirmed significant differences in structural features present in glass solutions prepared from pure amines (n-propylamine and n-butylamine) and their mixtures with methanol. The experiments with dissolved elemental sulfur and Ge25S75 glass analog proved that both antimony and methanol presence induce further splitting of the Ge4S104- cluster structure, which fundamentally affects the properties of deposited thin films. Significant structural and compositional differences were found not only in solutions and as-prepared samples, but also after thin films’ thermal treatment (hard baking up to 210°C). The as-prepared thin films deposited from amine-methanol mixtures possessed the exact composition of source bulk glass while thin films of other solvent formulations exhibited sulfur deficiency. The annealing up to 210°C only highlighted this difference. As a result of the different structure of the thin films prepared in this way, the other benefits of methanol addition were found, namely an increase in the refractive index by approx. 0.1 independent of the annealing temperature, or a lower thermally induced thickness contraction (up to 7.5%). 

Abstract Phase-change materials, demonstrating a rapid switching between two distinct states with a sharp contrast in electrical, optical or magnetic properties, are vital for modern photonic and electronic devices. To date, this effect is observed in chalcogenide compounds based on Se, Te or both, and most recently in stoichiometric Sb 2 S 3 composition. Yet, to achieve best integrability into modern photonics and electronics, the mixed S/Se/Te phase change medium is needed, which would allow a wide tuning range for such important physical properties as vitreous phase stability, radiation and photo-sensitivity, optical gap, electrical and thermal conductivity, non-linear optical effects, as well as the possibility of structural modification at nanoscale. In this work, a thermally-induced high-to-low resistivity switching below 200 °C is demonstrated in Sb-rich equichalcogenides (containing S, Se and Te in equal proportions). The nanoscale mechanism is associated with interchange between tetrahedral and octahedral coordination of Ge and Sb atoms, substitution of Te in the nearest Ge environment by S or Se, and Sb–Ge/Sb bonds formation upon further annealing. The material can be integrated into chalcogenide-based multifunctional platforms, neuromorphic computational systems, photonic devices and sensors.