A"Burnt Bridge'' Brownian Ratchet
نویسندگان
چکیده
Motivated by a biased diffusion of molecular motors with the bias dependent on the state of the substrate, we investigate a random walk on a one-dimensional lattice that contains weak links (called " bridges ") which are affected by the walker. Namely, a bridge is destroyed with probability p when the walker crosses it; the walker is not allowed to cross it again and this leads to a directed motion. The velocity of the walker is determined analytically for equidistant bridges. The special case of p = 1 is more tractable — both the velocity and the diffusion constant are calculated for uncorrelated locations of bridges, including periodic and random distributions.
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