Berry-phase theory of proper piezoelectric response
نویسندگان
چکیده
منابع مشابه
Berry Phase and Supersymmetry
We study the constraints of supersymmetry on the non-Abelian holonomy given by U = P exp(i ∫ A), the path-ordered exponential of a connection A. For theories with four supercharges, we show that A satisfies the tt* equations if it is a function of chiral multiplets. In contrast, when A is a function of vector multiplets, it satisfies the Bogomolnyi monopole equations. We describe applications o...
متن کاملElastic Properties and Enhanced Piezoelectric Response at Morphotropic Phase Boundaries
The search for improved piezoelectric materials is based on the morphotropic phase boundaries (MPB) between ferroelectric phases with different crystal symmetry and available directions for the spontaneous polarization. Such regions of the composition x - T phase diagrams provide the conditions for minimal anisotropy with respect to the direction of the polarization, so that the polarization ca...
متن کاملBerry phase in magnetic superconductors.
In magnetic systems, electronic bands often acquire nontrivial topological structure characterized by gauge flux distribution in momentum k space. It sometimes follows that the phase of the wave functions cannot be defined uniquely over the whole Brillouin zone. In this Letter, we develop a theory of superconductivity in the presence of this gauge flux both in two- and three-dimensional systems...
متن کاملSome geometric features of Berry ́s phase
In this letter, we elaborate on the identification and construction of the differential geometric elements underlying Berry ́s phase. Berry bundles are built generally from the physical data of the quantum system under study. We apply this construction to typical and recently investigated systems presenting Berry ́s phase to explore their geometric features. Berry ́s phase [1] discovery for parame...
متن کاملBerry Phase of a Resonant State
We derive closed analytical expressions for the complex Berry phase of an open quantum system in a state which is a superposition of resonant states and evolves irreversibly due to the spontaneous decay of the metastable states. The codimension of an accidental degeneracy of resonances and the geometry of the energy hypersurfaces close to a crossing of resonances differ significantly from those...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Physics and Chemistry of Solids
سال: 2000
ISSN: 0022-3697
DOI: 10.1016/s0022-3697(99)00273-5