Saved in:
Bibliographic Details
Main Authors: Wentzcovitch, Renata, Cobden, Laura, Houser, Christine, Shephard, Grace, Zhuang, Jingyi
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2603.20812
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911534424260608
author Wentzcovitch, Renata
Cobden, Laura
Houser, Christine
Shephard, Grace
Zhuang, Jingyi
author_facet Wentzcovitch, Renata
Cobden, Laura
Houser, Christine
Shephard, Grace
Zhuang, Jingyi
contents The Earth's lower mantle hosts a subtle but pervasive quantum phenomenon: the pressure-induced spin crossover of iron in its dominant minerals, bridgmanite and ferropericlase. In this transition, iron ions gradually shift from high-spin to low-spin electronic states without structural change, altering their volume, compressibility, and elastic properties. Although long recognized experimentally and theoretically, its geophysical significance has only recently become clear through the integration of mineral physics and three-dimensional seismic imaging. The spin crossover reduces bulk modulus and P-wave velocities while leaving S-wave speeds largely unaffected, producing a distinctive decoupling between P- and S-wave anomalies. This signature is now observed in global tomography and reconciles seismic observations with realistic mantle temperatures and compositions. Rather than forming a sharp boundary, the crossover extends across most of the lower mantle, acting as a diffuse yet essential control on seismic structure. This work highlights how quantum-scale electronic transitions influence planetary-scale dynamics and interpretations of Earth's deep interior.
format Preprint
id arxiv_https___arxiv_org_abs_2603_20812
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A quiet quantum revolution in Earth's deep interior
Wentzcovitch, Renata
Cobden, Laura
Houser, Christine
Shephard, Grace
Zhuang, Jingyi
Geophysics
Materials Science
The Earth's lower mantle hosts a subtle but pervasive quantum phenomenon: the pressure-induced spin crossover of iron in its dominant minerals, bridgmanite and ferropericlase. In this transition, iron ions gradually shift from high-spin to low-spin electronic states without structural change, altering their volume, compressibility, and elastic properties. Although long recognized experimentally and theoretically, its geophysical significance has only recently become clear through the integration of mineral physics and three-dimensional seismic imaging. The spin crossover reduces bulk modulus and P-wave velocities while leaving S-wave speeds largely unaffected, producing a distinctive decoupling between P- and S-wave anomalies. This signature is now observed in global tomography and reconciles seismic observations with realistic mantle temperatures and compositions. Rather than forming a sharp boundary, the crossover extends across most of the lower mantle, acting as a diffuse yet essential control on seismic structure. This work highlights how quantum-scale electronic transitions influence planetary-scale dynamics and interpretations of Earth's deep interior.
title A quiet quantum revolution in Earth's deep interior
topic Geophysics
Materials Science
url https://arxiv.org/abs/2603.20812