12 research outputs found
Entanglement and Density Matrix of a Block of Spins in AKLT Model
We study a 1-dimensional AKLT spin chain, consisting of spins in the bulk
and at both ends. The unique ground state of this AKLT model is described
by the Valence-Bond-Solid (VBS) state. We investigate the density matrix of a
contiguous block of bulk spins in this ground state. It is shown that the
density matrix is a projector onto a subspace of dimension . This
subspace is described by non-zero eigenvalues and corresponding eigenvectors of
the density matrix. We prove that for large block the von Neumann entropy
coincides with Renyi entropy and is equal to .Comment: Revised version, typos corrected, references added, 31 page
Glycoprotein nature of surface molecules of effector cells with lymphokine activated killer (LAK) activity. Evidence that T11, T8 or T3 molecules are not involved in tumor cell lysis by LAK effector cells
Diffusional and vibrational properties of water confined in very thin nanoporous glasses probed by light and neutron scattering
Rayleigh-wing, Raman and quasi-elastic neutron scattering data on water confined into nanoporous
glasses (silica 26 Å pores), are presented and discussed. The H-bond among water molecules and Si-OH surface
groups originates strong hydration effects, that induce more stable structural environments in which the memory of
collective modes (the [Math]60 cm-1 and [Math]190 cm-1 shoulders due to the HB bending and HB stretching modes of water)
is lost and the O-H stretching band connected to low-density water tends to disappear. The quasi-elastic neutron
response is explained in terms of two available current models : the Dianoux-Volino model and the MCT model