Tunnel Diodes

Abstract

The magnetic properties of the antiferromagnet CeNiSnH and of the ferromagnet CeNiSnH 1.8 on hydrostatic pressure (0 P 10.8 bar) have been determined using a miniature piston-cylinder CuBe pressure cell. With increasing P, the Néel temperature of CeNiSnH increases weakly from 4.77 to 5.01 K whereas the Curie temperature of CeNiSnH 1.8 decreases rapidly from 7.16 to 5.30 K. Similar pressure dependence is also observed in the critical field of the metamagnetic transition of CeNiSnH and in the coercive field of CeNiSnH 1.8 . Electronic structure calculations for these hydrides within the density functional theory show agreement with the experimental findings. Detailed examination of the chemical bonding features point to the conclusion that the antibonding Ce-Ni states below the Fermi level for CeNiSnH 1.8 could be responsible for the decrease of its Curie temperature under applied pressure.

Hole Diffusion Lengths in VPE GaAs and GaAs0.6 P 0.4 Treated with Transition Metals

“…Ni acceptor levels in GaAs are usually reported at Ev + 0.35 or 0.42 eV (62,63), with questionable levels at 0.08, 0.15, 0.2, and 0.53 eV (63)(64)(65). Our studies of Ni in VPE GaAs show acceptor levels at E~ + 0.39 eV and Ec --0.39 eV.…”

Josephson phase diffusion in small Josephson junctions: a strongly nonlinear regime

“…By making use of the method proposed and elaborated in [12,15] we obtain the correlation function ρ(t) in the following form…”