Entanglement Chern number for three-dimensional topological insulators: Characterization by Weyl points of entanglement Hamiltonians

We propose characterization of the three-dimensional topological insulator by using the Chern number for the entanglement Hamiltonian (entanglement Chern number). Here we take the extensive spin partition of the system, that pulls out the quantum entanglement between up spin and down spin of the many-body ground state. In three dimensions, the topological insulator phase is described by the section entanglement Chern number, which is the entanglement Chern number for a periodic plane in the Brillouin zone. The section entanglement Chern number serves as an interpolation of the Z2 invariants defined on time-reversal invariant planes. We find that the change of the section entanglement Chern number protects the Weyl point of the entanglement Hamiltonian, and the parity of the number of Weyl points distinguishes the strong topological insulator phase from the weak topological insulator phase

Detection of vanadyl-nitrogen interaction in organs of the vanadyl-treated rat: electron spin echo envelope modulation study

AbstractESEEM spectroscopy was applied for the first time to organs of an animal, viz. the kidney and liver of the rat treated with vanadyl sulfate. The aim of this study is to investigate the in vivo coordination structure of vanadyl ions administrated, and to gain information concerning the insulin-mimic activity of vanadium. ESEEM measurements for kidney and liver performed at 77 K have established nitrogen coordination to a certain percentage of vanadyl ion in the organs. The rotios of nitrogen-coordinating vanadyl ion were estimated as 70–80% in the liver, and 50–55% in the kidney. Isotropic portions of the 14N HFC were estimated as |Aiso| ∼ 5.0 MHz for liver, and ∼ 5.2 MHz for kidney, indicating that the coordinating nitrogen is an amino nitrogen. Coordination of the Lys ϵ-amine or the N-terminal α-amine of a protein or (a peptide) to vanadyl ion in vivo is suggested

Entanglement Chern Number of the Kane–Mele Model with Ferromagnetism

The entanglement Chern number, the Chern number for the entanglement Hamiltonian, is used to characterize the Kane–Mele model, which is a typical model of the quantum spin Hall phase with time-reversal symmetry. We first obtain the global phase diagram of the Kane–Mele model in terms of the entanglement spin Chern number, which is defined by using a spin subspace as a subspace to be traced out in preparing the entanglement Hamiltonian. We further demonstrate the effectiveness of the entanglement Chern number without time-reversal symmetry by extending the Kane–Mele model to include the Zeeman term. The numerical results confirm that the sum of the entanglement spin Chern number is equal to the Chern number