Conductance Spectra of Carbyne Transverse to Carbon Chains. Is It Related to the Soliton Lattice?

The influence of the thickness of an oriented carbyne film on the conductance of a special sample was investigated with an electric field of up to 1.8 ⋅ 10⁶ V/cm applied transverse to the carbon chains. A steplike dependence of the conductance on the thickness was observed. The general shape of the current-voltage characteristics, I ∝ U^2.3, changes to I ∝ U² when the thickness corresponding to a rapid change of conductance is attained. The characteristics presumably correspond to the space-charge limited current in the presence or absence of the trap band within the carbyne band gap. We propose the formation of a charge-topological soliton lattice at “magic” thicknesses which results in a layered structure of the film and in a bandlike conduction transverse to the chains.