Hydrogen-assisted stabilization of Ni nanowires in solution

We have studied conductance characteristics of mechanically fabricated Ni nanoconstrictions under controlling electrochemical potential and pH of the electrolyte. Conductance histogram showed clear feature peaked at 1-1.5 $G_{0}$ (=$2e^{2}/h$) when the potential of the constriction was kept at more negative potential than -900 mV vs. Ag/AgCl in pH=3.7. Comparable feature also appeared at more positive potential when lower pH solution was used. We have revealed that Ni mono atomic contact or mono atomic wire can be stabilized in solution at room temperature under the hydrogen evolution.Comment: 4 pages, 3 figures; to appear in Appl. Phys. Let

Parallelizing multiple precision Taylor series method for integrating the Lorenz system

A hybrid MPI+OpenMP strategy for parallelizing multiple precision Taylor series method is proposed, realized and tested. To parallelize the algorithm we combine MPI and OpenMP parallel technologies together with GMP library (GNU miltiple precision libary) and the tiny MPIGMP library. The details of the parallelization are explained on the paradigmatic model of the Lorenz system. We succeed to obtain a correct reference solution in the rather long time interval - [0,7000]. The solution is verified by comparing the results for 2700-th order Taylor series method and precision of ~ 3374 decimal digits, and those with 2800-th order and precision of ~ 3510 decimal digits. With 192 CPU cores in Nestum cluster, Sofia, Bulgaria, the 2800-th order computation was ~ 145 hours with speedup ~ 105.Comment: arXiv admin note: text overlap with arXiv:1908.0930