Tilt-Induced Anisotropic to Isotropic Phase Transition at 1⁄4 5=2
نویسندگان
چکیده
A modest in-plane magnetic field Bk is sufficient to destroy the fractional quantized Hall states at 1⁄4 5=2 and 7=2 and replace them with anisotropic compressible phases. Remarkably, we find that at larger Bk these anisotropic phases can themselves be replaced by isotropic compressible phases reminiscent of the composite fermion fluid at 1⁄4 1=2. We present strong evidence that this transition is a consequence of the mixing of Landau levels from different electric subbands. We also report surprising dependences of the energy gaps at 1⁄4 5=2 and 7=3 on the width of the confinement potential.
منابع مشابه
Deformable particles with anisotropic interactions: unusual field-induced structural transitions in ultrasoft ionic microgel colloids†
Ionic microgels are intriguing soft and deformable colloids with an effective pair potential that crosses over from Yukawa-like at large distances to a much softer repulsive interaction at short distances. Here we report the effect of adding an anisotropic dipolar contribution to colloids with such ‘‘ultra-soft’’ interactions. We use an alternating electric field to induce a tunable dipolar con...
متن کاملInvestigation into the temperature dependence of isotropic- nematic phase transition of Gay- Berne liquid crystals
Density functional approach was used to study the isotropic- nematic (I-N) transition and calculate the values of freezing parameters of the Gay- Berne liquid crystal model. New direct and pair correlation functions of a molecular fluid with Gay- Berne pair potential were used. These new functions were used in density functional theory as input to calculate the isotropic- nematic transition den...
متن کاملVelocity Modeling in a Vertical Transversely Isotropic Medium Using Zelt Method
In the present paper, the Zelt algorithm has been extended for ray tracing through an anisotropic model. In anisotropic media, the direction of the propagated energy generally differs from that of the plane-wave propagation. This makes velocity values to be varied in different directions. Therefore, velocity modeling in such media is completely different from that in an isotropic media. The vel...
متن کاملEscape configuration lattice near the nematic-isotropic transition: tilt analogue of blue phases.
We predict the possible existence of a new phase of liquid crystals near the nematic-isotropic transition. This phase is an achiral, tilt analogue of the blue phase and is composed of a lattice of double-tilt, escape-configuration cylinders. We discuss the structure and the stability of this phase and provide an estimate of the lattice parameter.
متن کاملLattice Model for a Binary Mixture of Hard Rods and Hard Cubes. Application to Solute Induced Nematic Isotropic Transitions
— A statistical mechanical treatment for a two component mixture of hard rods of dimensions L% lx 1 (L = 5.10) and hard cubes of dimensions D* Dx D (1 =s D =S 2), placed on a simple cubic lattice, is described. The dimensionless pressure-to-temperature ratio 0 = Pvo/kT (where vo is the volume of a lattice site) is chosen so that the system is anisotropic when only rods are present. At constant ...
متن کامل