Supersymmetry and multicriticality in a ladder of constrained fermions

Supersymmetric lattice models of constrained fermions are known to feature exotic phenomena such as superfrustration, with an extensive degeneracy of ground states, the nature of which is however generally unknown. Here we address this issue by considering a superfrustrated model, which we deform from the supersymetric point. By numerically studying its two-parameter phase diagram, we reveal a rich phenomenology. The vicinity of the supersymmetric point features period-4 and period-5 density waves which are connected by a floating phase (incommensurate Luttinger liquid) with smoothly varying density. The supersymmetric point emerges as a multicritical point between these three phases. Inside the period-4 phase we report a valence-bond solid type ground state that persists up to the supersymmetric point. Our numerical data for transitions out of density-wave phases are consistent with the Pokrovsky-Talapov universality class. Furthermore, our analysis unveiled a period-3 phase with a boundary determined by a competition between single and two-particle instabilities accompanied by a doubling of the wavevector of the density profiles along a line in the phase diagram.

Key Technology of Construction for Middle Tower of Three-Tower and Two-Span Suspension Bridge

Tai-Zhou Bridge, which has a three-tower and two-span, is 1080 meters long and 2 meters wide. The middle tower is a huge caisson foundation and chevron steel tower structure. It is important to make some effective technical measures to control the processes of caisson foundation’s installation, such as floating, orientation, implantation and final sunk, especially in complex conditions. Eroding model tests for the caisson foundation’s floating phase and sunken phase play an important role in the prophase installation. Information control technology could exactly guidance the sunk of cession. Finally, the linkage control of steel tower’s manufacture and operation is necessary for the precision of installation.