Fragile 3D Order in V_{1-x}Mo_{x}O_{2}

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid-State Chemistry

Background:

• The metal-insulator transition in rutile Vanadium Dioxide (VO_{2}) is complex due to intertwined electron correlations and atomic structure.
• Understanding this transition is crucial for developing advanced electronic materials.

Purpose of the Study:

• To investigate the structural changes and emergent order in Molybdenum-doped Vanadium Dioxide (V_{1-x}Mo_{x}O_{2}).
• To characterize the transition from a 3D ordered phase to a novel 2D frustrated order.

Main Methods:

• Single crystal diffuse x-ray scattering was employed to analyze the structural properties.
• The study focused on V_{1-x}Mo_{x}O_{2} at doping concentrations x=0.17 and x=0.19.

Main Results:

• A sudden collapse of three-dimensional order was observed at x=0.17.
• A novel frustrated two-dimensional order emerged at x=0.19, with minimal changes in electronic properties.
• Long-range structural correlations were found along (11L) planes, with short-range correlations transverse to these planes.

Conclusions:

• The findings indicate a transition from the 3D M1 phase to a 2D variant of the M2 phase in V_{1-x}Mo_{x}O_{2}.
• This two-dimensionality arises from a unique form of geometric frustration, primarily structural in origin.