# Observation of weakened V-V dimers in the monoclinic metallic phase of strained VO2

## TL;DR

This study uses spectromicroscopy to reveal that in strained VO2, the long-range order of V-V dimers weakens at mesoscopic scales near the MIT, while electrical conductivity transitions uniformly.

## Contribution

It uncovers the dissociation of V-V dimer order from crystal symmetry at mesoscopic scales in strained VO2, providing new insights into the MIT mechanism.

## Key findings

- Long-range V-V dimer order weakens beyond ~200 nm.
- Conductivity transition remains homogeneous in a narrow temperature window.
- Mesoscopic stripe order involves periodic modulations in symmetry and dimerization.

## Abstract

Emergent order at mesoscopic length scales in condensed matter can provide fundamental insight into the underlying competing interactions and their relationship with the order parameter. Using spectromicroscopy, we show that mesoscopic stripe order near the metal-insulator transition (MIT) of strained VO2 represent periodic modulations in both crystal symmetry and V-V dimerization. Above the MIT, we unexpectedly find the long range order of V-V dimer strength and crystal symmetry become dissociated beyond ~ 200 nm, whereas the conductivity transition proceeds homogeneously in a narrow temperature range.