158 citations · 422 across the 10 of their papers we have counts for
10 papers
Giant Spin Lifetime Anisotropy and Spin-Valley Locking in Silicene and Germanene from First-Principles Density-Matrix Dynamics
Junqing Xu, Hiroyuki Takenaka, Adela Habib +2
Through First-Principles real-time Density-Matrix (FPDM) dynamics simulations, we investigate spin relaxation due to electron-phonon and electron-impurity scatterings with spin-orb…
Stable Polar Oxynitrides through Epitaxial Strain
Li Zhu, Hiroyuki Takenaka, R. E. Cohen
We investigate energetically favorable structures of ABON oxynitrides as functions of pressure and strain via swarm-intelligence-based structure prediction methods, DFT lattice…
Magnetoelectric control of topological phases in graphene
Hiroyuki Takenaka, Shane Sandhoefner, Alexey A. Kovalev +1
Topological antiferromagnetic (AFM) spintronics is an emerging field of research, which involves the topological electronic states coupled to the AFM order parameter known as the N…
First-principles studies of the local structure and relaxor behavior of Pb(MgNb)O-PbTiO-derived ferroelectric perovskite solid solutions
Hengxin Tan, Hiroyuki Takenaka, Changsong Xu +3
We have investigated the effect of transition metal dopants on the local structure of the prototypical 0.75 Pb(MgNb)O-0.25 PbTiO relaxor ferroelectric. We f…
First-principles calculation of bulk photovoltaic effect in CHNHPbI and CHNHPbICl
Fan Zheng, Hiroyuki Takenaka, Fenggong Wang +2
Hybrid halide perovskites exhibit nearly 20% power conversion efficiency, but the origin of their high efficiency is still unknown. Here, we compute the shift current, a dominant m…
Density Functional Theory Study Of Hypothetical PbTiO3-Based Oxysulfides
John A. Brehm, Hiroyuki Takenaka, Chan-Woo Lee +4
Using density functional theory (DFT) within the local density approximation (LDA), we calculate the physical and electronic properties of PbTiO3 (PTO) and a series of hypothetical…
Anisotropic Local Correlations and Dynamics in a Relaxor Ferroelectric
Hiroyuki Takenaka, Ilya Grinberg, Andrew M. Rappe
Relaxor ferroelectrics have been a focus of intense attention due to their anomalous dielectric characteristics, diffuse phase transitions, and strong piezoelectricity. Understandi…
Reinterpretation of bond-valence model with bond-order formalism: an improved bond-valence based interatomic potential for PbTiO
Shi Liu, Ilya Grinberg, Hiroyuki Takenaka +1
We present a modified bond-valence model of PbTiO based on the principles of bond-valence and bond-valence vector conservation. The relationship between the bond-valence model…
Post density functional theoretical studies of highly polar semiconductive Pb(TiNi)O solid solutions: The effects of cation arrangement on band gap
Gaoyang Gou, Joseph W. Bennett, Hiroyuki Takenaka +1
We use a combination of conventional density functional theory (DFT) and post-DFT methods, including the local density approximation plus Hubbard (LDA+), PBE0, and self-cons…
Bonding of H in O vacancies of ZnO
H. Takenaka, D. J. Singh
We investigate the bonding of H in O vacancies of ZnO using density functional calculations. We find that H is anionic and does not form multicenter bonds with Zn in this compound.