title: Spherical nematic shells with a threefold valence.
abstract: We present a theoretical study of the energetics of thin nematic shells with two charge-one-half defects and one charge-one defect. We determine the optimal arrangement: the defects are located on a great circle at the vertices of an isosceles triangle with angles of 66^{∘} at the charge-one-half defects and a distinct angle of 48^{∘}, consistent with experimental findings. We also analyze thermal fluctuations around this ground state and estimate the energy as a function of thickness. We find that the energy of the three-defect shell is close to the energy of other known configurations having two charge-one and four charge-one-half defects. This finding, together with the large energy barriers separating one configuration from the others, explains their observation in experiments as well as their long-time stability.
authors: Instituut-Lorentz for Theoretical Physics, Leiden University, Leiden NL 2333 CA, The Netherlands.
authors: Vinzenz
authors: V
authors: Koning
authors: EC2M, UMR Gulliver CNRS-ESPCI 7083 10 Rue Vauquelin, F-75231 Paris Cedex 05, France.
authors: Teresa
authors: T
authors: Lopez-Leon
authors: EC2M, UMR Gulliver CNRS-ESPCI 7083 10 Rue Vauquelin, F-75231 Paris Cedex 05, France.
authors: Alexandre
authors: A
authors: Darmon
authors: School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors: Alberto
authors: A
authors: Fernandez-Nieves
authors: Instituut-Lorentz for Theoretical Physics, Leiden University, Leiden NL 2333 CA, The Netherlands.
authors: V
authors: V
authors: Vitelli