Combined field ion and electron microscopy and mass-spectrometry have revealed the presence of linear carbon chains at the surface of sharpened carbon fibers treated by electric fields of the order of 1011 V m−1. Linear chains attached to carbon tips consisting of more than ten atoms can be produced in situ in a field emission microscope using low-temperature pulsed-voltage field evaporation. The process of field evaporation is sporadic with an anomalously large instant rate of evaporation. Current versus voltage field electron characteristics of monoatomic carbon wires were investigated. By employing molecular dynamics simulation it was shown that atomic C-chains can be produced during the high-field unraveling of nanofibers. These chains are perfectly resolved both in electron and ion modes of the field emission microscope.

Field ion microscopic imaging of monatomic carbon chains near the ground quantum states and the visualization of their two-dimensional wave functions were demonstrated. Quantum motions with the frequency proportional to the electric field are detected and analyzed with subangstrom lateral resolution. Electric fields above 10(10) V/m can be used for control of a transverse vibration mode of atomic chains in the terahertz spectral range.

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Linear forms of carbon are important in a wide variety of applications, ranging from highly conducting interconnects to field emission materials. By methods of field ion microscopy (FIM) and mass-spectrometry, it was revealed that linear carbon chains were present at the surface of carbon fibers after high-voltage treatment. The carbon chains attached to the specimen tips were produced in situ in a field ion microscope by unraveling of nanofibers using low-temperature evaporation in electric fields of the order of 1011 Vm-1. The unraveling of graphite is possible due to the ultimate strength of the monoatomic carbon chain. The maximum force before failure of carbon chains at 0 K is 7.916 nN at a strain of 0.19 and the ideal tensile strength is equal to 252.1 GPa. Molecular dynamics simulations and high resolution FIM experiments are performed to assess the evaporation of atomic chains under high-field conditions. One can conclude that ions are field evaporated from a graphite surface initially in linear cluster forms, which decompose mostly into smaller atomic clusters and individual ions because of the ultrahigh-temperature excitation during unraveling.