Steering chiral swimmers along noisy helical paths

Benjamin M. Friedrich; Frank Jülicher

doi:10.1103/physrevlett.103.068102

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arXiv · 0903.0930

Steering chiral swimmers along noisy helical paths

Benjamin M. Friedrich·Frank Jülicher

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Abstract

Chemotaxis along helical paths towards a target releasing a chemoattractant is found in sperm cells and many microorganisms. We discuss the stochastic differential geometry of the noisy helical swimming path of a chiral swimmer. A chiral swimmer equipped with a simple feedback system can navigate in a concentration gradient of chemoattractant. We derive an effective equation for the alignment of helical paths with a concentration gradient which is related to the alignment of a dipole in an external field. We discuss the chemotaxis index in the presence of fluctuations.

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Benjamin M. Friedrich, Frank Jülicher. 2009-03-05. Steering chiral swimmers along noisy helical paths. https://doi.org/10.1103/physrevlett.103.068102

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