Zhi-Cheng Yang
University of Maryland, College Park
Quantum entanglementPhysicsTopologyGauge symmetryEigenstate thermalization hypothesisQuantum stateHamiltonian (quantum mechanics)Computational problemQubitTheoretical physicsComputer scienceSymmetry (physics)ComputationIsing modelThermodynamic limitFloquet theoryQuantum computerQuantum mechanicsRandom matrixVertex modelQuantumQuantum annealing
40Publications
10H-index
370Citations
Publications 34
#1Shao-Kai Jian (UMD: University of Maryland, College Park)H-Index: 15
#2Zhi-Cheng Yang (UMD: University of Maryland, College Park)H-Index: 10
Last. Xiao Chen (BC: Boston College)H-Index: 21
view all 4 authors...
We show that a class of \mathcal{PT}symmetric non-Hermitian Hamiltonians realizing the Yang-Lee edge singularity exhibits an entanglement transition in the long-time steady state evolved under the Hamiltonian. Such a transition is induced by a level crossing in the imaginary part of the eigenenergies between the ground state and some highly excited state, and hence is first-order in nature. At the transition, the entanglement entropy of the steady state jumps discontinuously from a volume-law...
#1DinhDuy Vu (UMD: University of Maryland, College Park)H-Index: 4
#2Rui-Xing Zhang (UT: University of Tennessee)H-Index: 14
Last. S. Das Sarma (UMD: University of Maryland, College Park)H-Index: 126
view all 4 authors...
#1Kai-Hsin Wu (BU: Boston University)
#2Zhi-Cheng YangH-Index: 10
Last. Claudio ChamonH-Index: 53
view all 5 authors...
We study a generalization of the two-dimensional transverse-field Ising model, combining both ferromagnetic and antiferromagnetic two-body interactions, that hosts exact global and local Z2 gauge symmetries. Using exact diagonalization and stochastic series expansion quantum Monte Carlo methods, we confirm the existence of the topological phase in line with previous theoretical predictions. Our simulation results show that the transition between the confined topological phase and the deconfined ...
#1Zhi-Cheng Yang (UMD: University of Maryland, College Park)H-Index: 10
#2Dmitry Green (BU: Boston University)H-Index: 6
Last. Claudio Chamon (BU: Boston University)H-Index: 53
view all 0 authors...
#1Zhi-Cheng YangH-Index: 10
#2Yao-Dong LiH-Index: 21
Last. Xiao ChenH-Index: 21
view all 4 authors...
We explore a class of random tensor network models with stabilizer'' local tensors which we name Random Stabilizer Tensor Networks (RSTNs). For RSTNs defined on a two-dimensional square lattice, we perform extensive numerical studies of entanglement phase transitions between volume-law and area-law entangled phases of the one-dimensional boundary states. These transitions occur when either (a) the bond dimension Dof the constituent tensors is varied, or (b) the tensor network is subject to ...
#2Zhi-Cheng YangH-Index: 10
Last. Shenglong XuH-Index: 15
view all 6 authors...
Quantum many-body scars (QMBS) constitute a new quantum dynamical regime in which rare "scarred" eigenstates mediate weak ergodicity breaking. One open question is to understand the most general setting in which these states arise. In this work, we develop a generic construction that embeds a new class of QMBS, rainbow scars, into the spectrum of an arbitrary Hamiltonian. Unlike other examples of QMBS, rainbow scars display extensive bipartite entanglement entropy while retaining a simple entang...
#1Rui-Xing ZhangH-Index: 14
#2Zhi-Cheng YangH-Index: 10
We extend the notion of fragile topology to periodically-driven systems. We demonstrate driving-induced fragile topology in two different models, namely, the Floquet honeycomb model and the Floquet \piflux square-lattice model. In both cases, we discover a rich phase diagram that includes Floquet fragile topological phases protected by crystalline rotation or mirror symmetries, Floquet Chern insulators, and trivial atomic phases, with distinct boundary features. Remarkably, the transitions be...
#1DinhDuy VuH-Index: 4
#2Rui-Xing ZhangH-Index: 14
Last. Sankar Das SarmaH-Index: 24
view all 4 authors...
We develop a general theory for two-dimensional (2D) anomalous Floquet higher-order topological superconductors (AFHOTSC), which are dynamical Majorana-carrying phases of matter with no static counterpart. Despite the triviality of its bulk Floquet bands, an AFHOTSC generically features the simultaneous presence of corner-localized Majorana modes at both zero and \pi/Tquasi-energies, a phenomenon beyond the scope of any static topological band theory. We show that the key to AFHOTSC is its un...
#1Fangli LiuH-Index: 11
#2Zhi-Cheng YangH-Index: 10
Last. Alexey V. GorshkovH-Index: 55
view all 5 authors...
Controllable Rydberg atom arrays have provided new insights into fundamental properties of quantum matter both in and out of equilibrium. In this work, we study the effect of experimentally relevant positional disorder on Rydberg atoms trapped in a 2D square lattice under anti-blockade (facilitation) conditions. We show that the facilitation conditions lead the connectivity graph of a particular subspace of the full Hilbert space to form a 2D Lieb lattice, which features a singular flat band. Re...
#1Zhi-Cheng YangH-Index: 10
#2Dmitry GreenH-Index: 6
Last. Claudio ChamonH-Index: 53
view all 4 authors...
We show that a \mathbb{Z}_3quantum double can be realized in an array of superconducting wires coupled via Josephson junctions. With a suitably chosen magnetic flux threading the system, the inter-wire Josephson couplings take the form of a complex Hadamard matrix, which possesses combinatorial gauge symmetry -- a local \mathbb{Z}_3symmetry involving permutations and shifts by \pm 2\pi/3of the superconducting phases. The sign of the star potential resulting from the Josephson energy is ...