2025/08/14 by Yu, Qisheng, Liu, Boyu, Xiang, Hongjun +1
#Computational Physics (physics.comp-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2508.10380
Motivated by the complementary properties of vanadium-based ferromagnets and HfO2-based ferroelectrics, we propose a novel multiferroic oxide, VHfO4, through 50% Hf4+ substitution with V4+ in the ferroelectric Pca21 phase of HfO2. First-principles DFT calculations reveal that the Pca21-like VHfO4 phase exhibits dynamic stability and concurrent ferroic orders: robust ferroelectric polarization comparable to HfO2 and V-driven magnetism. Parallel tempering Monte Carlo simulations identify an antiferromagnetic ground state, while strain engineering enables tunable magnetoelectric coupling. Biaxial in-plane strain induces four magnetic states: intralayer FM/interlayer AFM, intralayer AFM/interlayer FM, spiral-like non-collinear order, and discrete alternating spin alignment. Critically, c-axis strain modulates magnetic energy landscapes, demonstrating electromechanical control of magnetism. This work establishes VHfO4 as a Type-I multiferroic with coexisting atomic-scale ferroic origins and strain-tunable cross-coupling, offering a platform for voltage-controlled spintronics devices.