Multi-platform static and dynamic compression and complete EOS modeling of ultra-wide bandgap semiconductor Ga₂O₃

Ga₂O₃ is a transparent semiconducting oxide with an ultra-large band gap. Its multiple low-symmetry

crystal structures and thermal anisotropy make experiments, density functional theory (DFT) simulations,

and equation of state (EOS) design challenging, which motivates us to push boundaries of both

experimental and modelling methods.

The inter-disciplinary topic of kinetics of dynamically driven phase transitions is at the forefront of

condensed matter physics, both for its theoretical importance and its relevance to technological

applications at extreme conditions of pressure and temperature.

We present, for Ga₂O₃ , quantitative, the atomic-scale kinetics of a dynamically driven phase transition,

alongside static and dynamic compression data, dynamic temperature measurements and new DFT

calculations at extreme conditions.

We leverage results from multiple experimental platforms: Z and Thor pulsed power facilities and the

STAR gas gun facility at SNL and HPCAT and DCS x-ray diffraction facilities at the Advanced Photon Source.

The various parts of the project come together in a multiphase, broad range EOS and the first wide-ranging

phase diagram for Ga₂O₃ , covering four solid phases and the liquid.