1,762 research outputs found
Cell attachment on Ion-implanted titanium surface
Of outmost importance for the successful use of an implant is a good adhesion of the surrounding tissue to the biomaterial. In addition to the surface composition of the implant, the surface topography also influences the properties of the adherent cells. In the present investigation, ion implanted and untreated surfaces were compared for cell adhesion and spreading. The surface topography of the surfaces were analyzed using AFM and the cell studies with SEM. The results of our present investigation is indicative of the fact that ion implanted titanium surface offer better cell binding affinity compared to untreated/polished surface
Disordered Chern insulator with a two step Floquet drive
We explore the physics of a Chern insulator subjected to a two step Floquet
drive. We analytically obtain the phase diagram and show that the system can
exhibit different topological phases characterized by presence and chirality of
edge-modes in the two bulk gaps of the Floquet quasienergy spectrum, around
and . We find that the phase of the system depends on the mean but not on
the amplitude of the drive. The bulk topological invariants characterizing the
phases can be extracted by mapping the unitary evolution within a time period
to an energetically trivial but topologically non-trivial time evolution. An
extensive numerical study of the bulk topological invariants in the presence of
quenched disorder reveals new transitions induced by strong disorder (i) from
the different topological to trivial insulator phases and (ii) from a trivial
to a topological Anderson insulator phase at intermediate disorder strengths.
Careful analysis of level statistics of the quasienergy spectrum indicates a
`levitation-annihilation' mechanism near these transitions.Comment: 15 pages, 10 figures, version published in Phys. Rev.
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