ナノスケールでのエントロピー生成を測定する新しい方法(New method to measure entropy production on the nanoscale)

2024-03-26 チャルマース工科大学

＜関連情報＞

• https://news.cision.com/chalmers/r/new-method-to-measure-entropy-production-on-the-nanoscale,c3951565
• https://www.nature.com/articles/s41467-023-44277-w

ポンプ・プローブ実験における超高速エントロピー生成 Ultrafast entropy production in pump-probe experiments

Lorenzo Caprini,Hartmut Löwen & R. Matthias Geilhufe
Nature Communications  Published:02 January 2024
DOI:https://doi.org/10.1038/s41467-023-44277-w

Abstract

The ultrafast control of materials has opened the possibility to investigate non-equilibrium states of matter with striking properties, such as transient superconductivity and ferroelectricity, ultrafast magnetization and demagnetization, as well as Floquet engineering. The characterization of the ultrafast thermodynamic properties within the material is key for their control and design. Here, we develop the ultrafast stochastic thermodynamics for laser-excited phonons. We calculate the entropy production and heat absorbed from experimental data for single phonon modes of driven materials from time-resolved X-ray scattering experiments where the crystal is excited by a laser pulse. The spectral entropy production is calculated for SrTiO₃ and KTaO₃ for different temperatures and reveals a striking relation with the power spectrum of the displacement-displacement correlation function by inducing a broad peak beside the eigenmode-resonance.