Optical investigations on the biaxial smectic- A phase of a bent-core compound.
Several unique optical properties have been obtained from freestanding films of a bent-core compound. Our experimental results indicate the existence of the antiferroelectric biaxial smectic-A (Sm A) phase. The critical exponent associated with the biaxiality through the uniaxial-antiferroelectric biaxial Sm A transition has been measured to be 0.82+/-0.04 , which is in good agreement with our theoretical calculation. Our theoretical advances further demonstrate that the critical behavior of the optical biaxiality with the order parameter being a vector is described by the secondary-order parameter of the three-dimensional XY model. We also observe a remarkable even-odd layering effect exhibited by the surface layers of freestanding films under an applied electric field (approximately 20 V/cm) in the film plane.
Wang
S T
ST
School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Han
X F
XF
Cady
A
A
Liu
Z Q
ZQ
Kamenev
A
A
Glazman
L
L
Sadashiva
B K
BK
Reddy
R Amaranatha
RA
Huang
C C
CC