Author's posts
Feb 14 2023
Extreme ultraviolet transient gratings: A tool for nanoscale photoacoustics
Collective lattice dynamics determine essential aspects of condensed matter, such as elastic and thermal properties. These exhibit strong dependence on the length-scale, reflecting the marked wavevector dependence of lattice excitations. The extreme ultraviolet transient grating (EUV TG) approach has demonstrated the potential of accessing a wavevector range corresponding to the 10s of nm length-scale, representing …
Feb 14 2023
Micro-Raman spectroscopy for a comprehensive understanding of the structural evolution of Basaltic-Andesite and Trachybasalt multiphase systems
The liquid viscosity of multiphase systems is usually retrieved by the use of combined chemical analysis and empirical chemistry-based models. Here we present an alternative approach to study the glassy pools in highly crystallized basaltic-andesite and trachybasalt samples obtained from isothermal crystallization experiment at different shear rates. Polarized micro-Raman spectra were collected at room temperature …
Feb 14 2023
Effect of the alkali vs iron ratio on glass transition temperature and vibrational properties of synthetic basalt-like glasses
Volcanic eruptions generate huge amounts of material with a wide range of compositions and therefore different physicochemical properties. We present a combined Raman and calorimetric study carried out on four synthetic basaltic glasses with different alkali vs iron ratio which spans the typical compositions of basalts on Earth. Differential scanning calorimetry shows that changes of this ratio …
Feb 13 2023
Amorphous-amorphous transformation induced in glasses by intense x-ray beams
The atomic displacements induced by an x-ray beam of relatively low energy, ε∼8 KeV, are investigated in pure boron oxide and in a set of sodium silicate glasses by means of x-ray photon correlation spectroscopy. We observe the complete x-ray induced transformation of the initial glass into a new amorphous state which remains stable under irradiation. The …
Jan 12 2023
Stochastic atomic acceleration during the X-ray-induced fluidization of a silica glass
The X-ray-induced, nonthermal fluidization of the prototypical SiO2 glass is investigated by X-ray photon correlation spectroscopy in the small-angle scattering range. This process is initiated by the absorption of X-rays and leads to overall atomic displacements which reach at least few nanometers at temperatures well below the glass transition. At absorbed doses of ∼5 GGy typical …