In a twisted nematic layer oppositely twisted regions can exist, separated by a disclination line, as demonstrated by the orientation of Williams domains. The disclination line can move under the influence of a magnetic field. Measurements of the velocity as a function of magnetic field strength and sample thickness lead to an estimate of the size of the disclination core. © 1973.
Gerritsma, C. J., Geurst, J. A., & Spruijt, A. M. J. (1973). Magnetic-field-induced motion of disclinations in a twisted nematic layer. Physics Letters A, 43(4), 356–358. https://doi.org/10.1016/0375-9601(73)90341-1