English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The boson peak (BP) is a universal feature in the Raman and inelasticscattering spectra of both disordered and crystalline materials. The currentparadigm presents the boson peak as the result of a Ioffe-Regel crossoverbetween ballistic (phonon) and diffusive-type excitations, where the loss ofcoherence of phonons is described as a purely harmonic process due tostructural disorder. This "harmonic disorder" paradigm for the BP has neverbeen challenged or tested at the atomistic level. Here, through a set ofatomistically-resolved characterizations of amorphous metallic alloys, weuncover a robust inverse proportionality between the intensity of boson peakand the activation energy of excitations in the potential energy landscape(PEL). Larger boson peak is linked with shallower basins and lower activationbarriers and, consequently, with strongly anharmonic sectors of the PEL.Numerical evidence from atomistic simulations indicates that THz atomicvibrations contributing the most to the BP in atomic glasses are stronglyanharmonic, as evidenced through very large values of the atomic- andmode-resolved Gr\"{u}neisen parameter found for the atomic vibrations thatconstitute the BP. These results provide a direct bridge between thevibrational spectrum and the topology of the PEL in solids, and point towards anew "giant anharmonicity" paradigm for both generic disordered materials andfor the phonon-glass problem in emerging materials for energy applications. Inthis sense, disorder and anharmonicity emerge as the two sides of the samecoin.

Correlation between vibrational anomalies and emergent anharmonicity of local potential energy landscape in metallic glasses