Observation of Emergent $\mathbb{Z}_2$ Gauge Invariance in a Superconducting Circuit

• URL: http://arxiv.org/abs/2111.05048v2
• Date: Mon, 20 Jun 2022 05:57:43 GMT
• Title: Observation of Emergent $\mathbb{Z}_2$ Gauge Invariance in a Superconducting Circuit
• Authors: Zhan Wang, Zi-Yong Ge, Zhongcheng Xiang, Xiaohui Song, Rui-Zhen Huang, Pengtao Song, Xue-Yi Guo, Luhong Su, Kai Xu, Dongning Zheng, and Heng Fan
• Abstract summary: We investigate the emergent $mathbbZ$ gauge invariance in a superconducting circuit with 10 transmon qubits. Despite the absence of gauge structure in the effective Hamiltonian, $mathbbZ$ gauge can still emerge in low-energy regimes.
• Score: 14.413924121049094
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Lattice gauge theories (LGTs) are one of the most fundamental subjects in many-body physics, and has recently attracted considerable research interests in quantum simulations. Here we experimentally investigate the emergent $\mathbb{Z}_2$ gauge invariance in a 1D superconducting circuit with 10 transmon qubits. By precisely adjusting staggered longitudinal and transverse fields to each qubit, we construct an effective Hamiltonian containing an LGT and gauge-broken terms. The corresponding matter sector can exhibit a localization, and there also exists a 3-qubit operator, of which the expectation value can retain nonzero for a long time in low-energy regimes. The above localization can be regarded as the confinement of matter fields, and the 3-body operator is the $\mathbb{Z}_2$ gauge generator. These experimental results demonstrate that, despite the absence of gauge structure in the effective Hamiltonian, $\mathbb{Z}_2$ gauge invariance can still emerge in low-energy regimes. Our work provides a method for both theoretically and experimentally studying the rich physics in quantum many-body systems with emergent gauge invariance.

Related papers

• Visualizing Dynamics of Charges and Strings in (2+1)D Lattice Gauge Theories [103.95523007319937]
  We study the dynamics of local excitations in a lattice of superconducting qubits. For confined excitations, the magnetic field induces a tension in the string connecting them. Our method allows us to experimentally image string dynamics in a (2+1)D LGT.
  arXiv  Detail & Related papers  (2024-09-25T17:59:05Z)
• $\mathbb{Z}_N$ lattice gauge theories with matter fields [0.0]
  We study fermions and bosons in $mathbb Z_N$ lattice gauge theories. We present analytical arguments for the most important phases and estimates for phase boundaries of the model.
  arXiv  Detail & Related papers  (2023-08-24T21:05:15Z)
• Small-time controllability for the nonlinear Schr\"odinger equation on $\mathbb{R}^N$ via bilinear electromagnetic fields [55.2480439325792]
  We address the small-time controllability problem for a nonlinear Schr"odinger equation (NLS) on $mathbbRN$ in the presence of magnetic and electric external fields. In detail, we study when it is possible to control the dynamics of (NLS) as fast as desired via sufficiently large control signals.
  arXiv  Detail & Related papers  (2023-07-28T21:30:44Z)
• Spin-$S$ $\mathrm{U}(1)$ Quantum Link Models with Dynamical Matter on a Quantum Simulator [3.1192594881563127]
  We present a bosonic mapping for the representation of gauge and electric fields with effective spin-$S$ operators. We then propose an experimental scheme for the realization of a large-scale spin-$1$ $mathrmU(1)$ QLM using spinless bosons in an optical superlattice.
  arXiv  Detail & Related papers  (2023-05-10T18:00:01Z)
• Spin Current Density Functional Theory of the Quantum Spin-Hall Phase [59.50307752165016]
  We apply the spin current density functional theory to the quantum spin-Hall phase. We show that the explicit account of spin currents in the electron-electron potential of the SCDFT is key to the appearance of a Dirac cone.
  arXiv  Detail & Related papers  (2022-08-29T20:46:26Z)
• Confinement-Induced Enhancement of Superconductivity in a Spin-$\frac{1}{2}$ Fermion Chain Coupled to a $\mathbb{Z}_2$ Lattice Gauge Field [0.0]
  In the odd-gauge sector, the superconducting model reduces to the Hubbard model with repulsive onsite interaction. We uncover how electric fields affect low-energy excitations by both analytical and numerical methods.
  arXiv  Detail & Related papers  (2022-08-15T10:03:27Z)
• Realistic scheme for quantum simulation of $\mathbb{Z}_2$ lattice gauge theories with dynamical matter in $(2+1)$D [0.0]
  We propose a realistic scheme for Rydberg atom array experiments in which a $mathbbZ$ gauge structure with dynamical charges emerges on experimentally relevant timescales. We discuss ground-state phase diagrams of the experimentally most effective $mathbbZ$ lattice gauge theories with dynamical matter. We present selected probes with immediate relevance, including signatures of disorder-free localization and a thermal deconfinement transition of two charges.
  arXiv  Detail & Related papers  (2022-05-17T18:00:00Z)
• Unimon qubit [42.83899285555746]
  Superconducting qubits are one of the most promising candidates to implement quantum computers. Here, we introduce and demonstrate a superconducting-qubit type, the unimon, which combines the desired properties of high non-linearity, full insensitivity to dc charge noise, insensitivity to flux noise, and a simple structure consisting only of a single Josephson junction in a resonator.
  arXiv  Detail & Related papers  (2022-03-11T12:57:43Z)
• Quantum Error Correction with Gauge Symmetries [69.02115180674885]
  Quantum simulations of Lattice Gauge Theories (LGTs) are often formulated on an enlarged Hilbert space containing both physical and unphysical sectors. We provide simple fault-tolerant procedures that exploit such redundancy by combining a phase flip error correction code with the Gauss' law constraint.
  arXiv  Detail & Related papers  (2021-12-09T19:29:34Z)
• Reliability of lattice gauge theories in the thermodynamic limit [0.0]
  In quantum-simulation implementations of gauge theories it is compromised by experimental imperfections. We numerically demonstrate that robust gauge invariance is also retained through a single-body gauge-protection term.
  arXiv  Detail & Related papers  (2021-04-14T18:00:04Z)
• Evolution of a Non-Hermitian Quantum Single-Molecule Junction at Constant Temperature [62.997667081978825]
  We present a theory for describing non-Hermitian quantum systems embedded in constant-temperature environments. We find that the combined action of probability losses and thermal fluctuations assists quantum transport through the molecular junction.
  arXiv  Detail & Related papers  (2021-01-21T14:33:34Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.