2024 New's Items

The gapped symmetric phase of the Affleck-Kennedy-Lieb-Tasaki model exhibits fractionalized spins at the ends of an open chain. We show that breaking SU(2) symmetry and applying a global spin-lowering dissipator achieves synchronization of these fractionalized spins. Additional local dissipators ensure convergence to the ground state manifold. In order to understand which aspects of this synchronization are robust within the entire Haldane-gap phase, we reduce the biquadratic term, which eliminates the need for an external field but destabilizes synchronization. Within the ground...

We consider two-dimensional (2d) quantum many-body systems with long-range orders, where the only gapless excitations in the spectrum are Goldstone modes of spontaneously broken continuous symmetries. To understand the interplay between classical long-range order of local order parameters and quantum order of long-range entanglement in the ground states, we study the topological point defects and textures of order parameters in such systems. We show that the universal properties of point defects and textures are determined by the remnant symmetry enriched topological order in the symmetry-...

A recent experiment on the bulk compound 4⁢Hb−TaS2 reveals an unusual time-reversal symmetry-breaking superconducting state that possesses a magnetic memory not manifest in the normal state. Here we provide a mechanism for this observation by studying the magnetic and electronic properties of 4⁢Hb−TaS2. We discuss the criterion for a small magnetization in the normal state in terms of spin and orbital magnetizations. Based on an analysis of lattice symmetry and Fermi surface structure, we propose that 4Hb−TaS2 realizes superconductivity in the interlayer, equal-spin channel with a gap...

Motivated by recent numerical studies reporting putative quantum paramagnetic behavior in spin-1/2 Heisenberg models on the maple-leaf lattice, we classify Abrikosov fermion mean-field Ansätze of fully symmetric U(1) and ℤ2 quantum spin liquids within the framework of projective symmetry groups. We obtain a total of 17⁢U⁡(1) and 12ℤ2 algebraic PSGs, and, upon restricting their realization via mean-field Ansätze with nearest-neighbor amplitudes (relevant to the studied models), only 12 U(1) and 8 ℤ2...