Theoretical Design of thermal spin molecular logic gates by using a combinational molecular junction

Based on the density functional theory combined with the non-equilibrium Green’s function methodology, we have studied the thermally-driven spin-dependent transport properties of a combinational molecular junction consisting of a planar four-coordinate Fe molecule and a 15,16-dinitrile dihydropyrene/cyclophanediene molecule with single-walled carbon nanotube bridge and electrode. Our results show that the magnetic field and light can effectively regulate the thermally-driven spin-dependent currents. Perfect thermal spin-filtering effect and good thermal switching effect are realized. The results are explained by the Fermi-Dirac distribution function, the spin-resolved transmission spectra, the spatial distribution of molecular projected self-consistent Hamiltonian orbitals, and the spin-resolved current spectra. On the basis of these thermally-driven spin-dependent transport properties, we further design three basic thermal spin molecular AND, OR and NOT gates.

Molecular Logic Gate Based on DNA Strand Displacement Reaction

In this paper, I construct an XOR logic gate based on DNA strand displacement reaction, and verify our design through corresponding biochemical experiment. I designed several different DNA strands. Based on two basic DNA strand displacement reaction mechanisms, by adding different input strands and taking the signal of FAM fluorescent group as the output, the XOR logic gate is realized. The result shows that DNA strand displacement technology has important application value in DNA computing, especially in the construction of DNA molecular logic gates.