Raman fingerprint of high-temperature superconductivity in compressed hydrides

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Dalladay-Simpson, Philip, Marchese, Guglielmo, Cao, Zi-Yu, Barone, Paolo, Benfatto, Lara, Garbarino, Gaston, Mauri, Francesco, Gorelli, Federico Aiace
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914157760086016
author Dalladay-Simpson, Philip
Marchese, Guglielmo
Cao, Zi-Yu
Barone, Paolo
Benfatto, Lara
Garbarino, Gaston
Mauri, Francesco
Gorelli, Federico Aiace
author_facet Dalladay-Simpson, Philip
Marchese, Guglielmo
Cao, Zi-Yu
Barone, Paolo
Benfatto, Lara
Garbarino, Gaston
Mauri, Francesco
Gorelli, Federico Aiace
contents The discovery of high-temperature superconductivity in hydrogen-rich compounds under extreme pressures has prompted great excitement, intense research, but also debate over the past decade. Electrical transport has been the primary diagnostic tool for identifying superconductivity in these systems, whereas complementary probes, including magnetic, spectroscopic, tunnelling and ultrafast methods, remain mostly qualitative due to experimental constraints and sample heterogeneity. Recent concerns over their reliability have fuelled controversy, leading to scepticism and pointing out the need for alternative, quantitative approaches. In this study, we acquired unprecedented high-quality Raman spectra of hexagonal LaH10 at approximately 145 GPa and low temperatures, in conjunction with electrical transport measurements. Upon cooling, we observe a drop of resistivity and simultaneous remarkable variations of phonon frequencies and linewidths. These effects are interpreted and perfectly reproduced by the Migdal-Eliashberg theory, providing a definitive proof of phonon-mediated superconductivity and enabling a quantitative determination of the superconducting energy gap. Our results establish Raman spectroscopy as a robust, contact-free probe with micrometric resolution for studying high temperature superconductivity, opening a powerful route to its discovery and characterization.
format Preprint
id arxiv_https___arxiv_org_abs_2511_10784
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Raman fingerprint of high-temperature superconductivity in compressed hydrides
Dalladay-Simpson, Philip
Marchese, Guglielmo
Cao, Zi-Yu
Barone, Paolo
Benfatto, Lara
Garbarino, Gaston
Mauri, Francesco
Gorelli, Federico Aiace
Superconductivity
Materials Science
The discovery of high-temperature superconductivity in hydrogen-rich compounds under extreme pressures has prompted great excitement, intense research, but also debate over the past decade. Electrical transport has been the primary diagnostic tool for identifying superconductivity in these systems, whereas complementary probes, including magnetic, spectroscopic, tunnelling and ultrafast methods, remain mostly qualitative due to experimental constraints and sample heterogeneity. Recent concerns over their reliability have fuelled controversy, leading to scepticism and pointing out the need for alternative, quantitative approaches. In this study, we acquired unprecedented high-quality Raman spectra of hexagonal LaH10 at approximately 145 GPa and low temperatures, in conjunction with electrical transport measurements. Upon cooling, we observe a drop of resistivity and simultaneous remarkable variations of phonon frequencies and linewidths. These effects are interpreted and perfectly reproduced by the Migdal-Eliashberg theory, providing a definitive proof of phonon-mediated superconductivity and enabling a quantitative determination of the superconducting energy gap. Our results establish Raman spectroscopy as a robust, contact-free probe with micrometric resolution for studying high temperature superconductivity, opening a powerful route to its discovery and characterization.
title Raman fingerprint of high-temperature superconductivity in compressed hydrides
topic Superconductivity
Materials Science
url https://arxiv.org/abs/2511.10784