Thermally induced local failures in quasi-one-dimensional systems: collapse in carbon nanotubes, necking in nanowires, and opening of bubbles in DNA.

We present a general framework to explore thermally activated failures in quasi-one-dimensional systems. We apply it to the collapse of carbon nanotubes, the formation of bottlenecks in nanowires, both of which affect conductance, and the opening of local regions or "bubbles" of base pairs in strands of DNA that are relevant for transcription and denaturation. We predict an exponential behavior for the probability of the opening of bubbles in DNA, the average distance between flattened regions of a nanotube or necking in a nanowire as a monotonically decreasing function of temperature, and compute a temperature below which these events become extremely rare.