Computational results of S–Au–S junction. The three I–V curves are (a) spin-up current, (b) spin-down current, and (c) total current at different distances. Panel (d) is the spin polarization P at a bias of 0.3 V. Panels (e)–(g) are the projected density of state (PDOS) of the center Au atom at the distance of (e) 3.2 Å, (f) 3.5 Å, and (g) 3.8 Å respectively. In panels (e)–(g), solid lines represent the PDOS of spin-up electron, dot lines represent the PDOS of spin-down electron, and the vertical dash lines represent the Fermi energy about −6.40 eV.