References of "Dahlgren, A"
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See detailAntiferroelectric liquid crystals with 45° tilt - a new class of promising electro-optic materials
D’havé, K.; Dahlgren, A; Rudquist, Per et al

in Ferroelectrics (2000), 244

Antiferroelectric liquid crystals with a tilt angle of 45 degrees have very interesting optical properties, which seem to have been overlooked so far perhaps because such materials have hardly been ... [more ▼]

Antiferroelectric liquid crystals with a tilt angle of 45 degrees have very interesting optical properties, which seem to have been overlooked so far perhaps because such materials have hardly been available. We have prepared a four-component mixture of partially fluorinated compounds with a SmC/sub n/* phase in the interval between 27.4 degrees C and 121.6 degrees C, in which the tilt angle theta saturates at 45 degrees for T<or=80 degrees C, and we investigate the optical properties, theoretically and experimentally. One of the surprising features of 45 degree materials is that they permit a remarkably high contrast by virtue of an excellent dark-state, in spite of the fact that AFLC materials are notoriously difficult to align. This is because a 45 degrees AFLC turns out to be (negatively) uniaxial instead of biaxial. We describe these properties and propose a number of potentially interesting new applications, including a polarizer-free display mode and a three-level ``phase-only'' modulator. [less ▲]

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See detailOptic, electrooptic and dielectric properties of novel antiferroelectric liquid crystal compounds
Jägemalm, P.; Lagerwall, Jan UL; Dahlgren, A et al

in Ferroelectrics (2000)

The optic, electrooptic and dielectric spectroscopy characterisation of novel four-ring thiophene-based chiral esters comprising suitably 5,5’-disubstituted 2,2’-bithiophene (antiferroelectrics) is ... [more ▼]

The optic, electrooptic and dielectric spectroscopy characterisation of novel four-ring thiophene-based chiral esters comprising suitably 5,5’-disubstituted 2,2’-bithiophene (antiferroelectrics) is reported. The two compounds exhibit interesting hysteresis in their phase sequences, and we show that even whole phases (e.g. their relatively wide ferri-phases) may be suppressed by the surface interactions in thin cells. [less ▲]

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