Bistability induced by crossed electric and magnetic fields in a nematic film
The static distortions in a homogeneously aligned nematic liquid-crystal film in crossed electric and magnetic fields are theoretically analyzed. Both fields are orthogonal to the undistorted molecular alignment and destabilizing. In the limit of small distortions, a first-order transition between two distorted configurations, with bistability and hysteresis, is obtained if the dielectric anisotropy parameter 1-epsilon/sub parallel//epsilon/sub perpendicular/ is lower than the elastic anisotropy parameter (k/sub 3/-k/sub 2/)/sup 2//(4k/sub 1/k/sub 2/), where k/sub 1/, k/sub 2/, and k/sub 3/ are the Frank elastic constants. This condition is satisfied by many commonly used nematic materials. At higher distortions an inversion point is found, above which the transition becomes of the second order. At this point a phenomenon similar to the critical opalescence of fluids is expected.
- Research Organization:
- Dipartimento di Fisica, Politecnico di Torino, Corso Duca degli Abruzzi 24, I-10129 Torino, Italy
- OSTI ID:
- 7089077
- Journal Information:
- Phys. Rev. A; (United States), Journal Name: Phys. Rev. A; (United States) Vol. 38:6; ISSN PLRAA
- Country of Publication:
- United States
- Language:
- English
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