Related papers: Metallicity-driven polar transitions in topologica…
Metals have high electronic conductivities, but very low Seebeck coefficients, which traditionally make them unsuitable for thermoelectric materials. Recent studies, however, showed that metals can deliver ultra-high thermoelectric power…
Tuning the spin-orbit coupling strength via foreign element doping and/or modifying bonding strength via strain engineering are the major routes to convert normal insulators to topological insulators. We here propose an alternative strategy…
Orbital angular momentum and torque transfer play central roles in a wide range of magnetic textures and devices including skyrmions and spin-torque electronics(1-4). Analogous topological structures are now also being explored in…
The temperature dependent thermoelectric power (TEP) of boron and nitrogen doped multi-walled carbon nanotube mats has been measured showing that such dopants can be used to modify the majority conduction from p-type to n-type. The TEP of…
The coupling of ferroelectricity and magnetic order provides rich tunability for engineering material properties and demonstrates great potential for uncovering novel quantum phenomena and multifunctional devices. Here, we report…
Oxide superlattices represent a potent avenue for tailoring emergent electronic phases through sophisticated interfacial charge transfer and dynamic lattice distortions. This study systematically investigates the structural and electronic…
We systematically investigate the effect of strain and doping on the polar metal phase in lithium osmate, LiOsO$_3$, using first-principles calculations. We demonstrate that the polar metal phase in LiOsO$_3$ can be controlled by biaxial…
The pentatellurides, ZrTe5 and HfTe5 are layered compounds with one dimensional transition-metal chains that show a never understood temperature dependent transition in transport properties as well as recently discovered properties…
Over the past decade, materials that combine broken inversion symmetry with metallic conductivity have gone from a thought experiment to one of the fastest growing research topics. In 2013, the observation of the first uncontested polar…
Topological insulators are a class of band insulators with non-trivial topology, a result of band inversion due to the strong spin-orbit coupling. The transition between topological and normal insulator can be realized by tuning the…
Motivated by recent studies on ferroelectric-like order coexisting with metallicity, we investigate ferroelectric (FE) superconductivity in which a FE-like structural phase transition occurs in the superconducting state. We consider a…
Modeling ferroelectric materials from first principles is one of the successes of density-functional theory, and the driver of much development effort, requiring an accurate description of the electronic processes and the thermodynamic…
We study from first-principles calculations the ferroelectric structural phase transition of Pb$_5$Ge$_3$O$_{11}$ crystal. The calculations of phonons and Born effective charges of the paraelectric phase allow us to identify a polar…
The phase diagram of a correlated material is the result of a complex interplay between several degrees of freedom, providing a map of the material's behavior. One can understand (and ultimately control) the material's ground state by…
Polar metals are rare because free carriers in metals screen electrostatic potential and eliminate internal dipoles. Degenerate doped ferroelectrics may create an approximate polar metallic phase. We use first-principles calculations to…
We study magnetic state and electron transport properties of composite multiferroic system consisting of a granular ferromagnetic thin film placed above the ferroelectric substrate. Ferroelectricity and magnetism in this case are coupled by…
The density driven Mott transition is studied by means of Dynamical Mean-Field Theory in the Hubbard-Holstein model, where the Hubbard term leading to the Mott transition is supplemented by an electron-phonon (e-ph) term. We show that an…
We studied the electrical transport on $\beta$-Fe$_{4+\delta}$Se$_{5}$ single-crystal nanowires, exhibiting $\sqrt{5}\times\sqrt{5}$ Fe-vacancy order and mixed valence of Fe. We observed a first-order metal-insulator transition of the…
Topological superconductivity has attracted intensive interest for its ability of hosting Majorana zero mode and implementing in topological quantum computations. Based on the first-principles calculations and the analysis of the effective…
Polar liquid crystals possess three dimensional orientational order coupled with unidirectional electric polarity, yielding fluid ferroelectrics. Such polar phases are generated by rod-like molecules with large electric dipole moments.…