Efficiently preparing Schr\"odinger's cat, fractons and non-Abelian topological order in quantum devices

• URL: http://arxiv.org/abs/2112.03061v2
• Date: Thu, 6 Jan 2022 17:31:14 GMT
• Title: Efficiently preparing Schr\"odinger's cat, fractons and non-Abelian topological order in quantum devices
• Authors: Ruben Verresen, Nathanan Tantivasadakarn, Ashvin Vishwanath
• Abstract summary: Long-range entangled quantum states -- like cat states and topological order -- are key for quantum metrology and information purposes. We propose how to scalably prepare a broad range of long-range entangled states with the use of existing experimental platforms. Remarkably, this protocol can prepare the 1D Greenberger-Horne-Zeilinger (GHZ) 'cat' state and 2D toric code with fidelity per site exceeding $0.9999$.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Long-range entangled quantum states -- like cat states and topological order -- are key for quantum metrology and information purposes, but they cannot be prepared by any scalable unitary process. Intriguingly, using measurements as an additional ingredient could circumvent such no-go theorems. However, efficient schemes are known for only a limited class of long-range entangled states, and their implementation on existing quantum devices via a sequence of gates and measurements is hampered by high overheads. Here we resolve these problems, proposing how to scalably prepare a broad range of long-range entangled states with the use of existing experimental platforms. Our two-step process finds an ideal implementation in Rydberg atom arrays, only requiring time-evolution under the intrinsic atomic interactions, followed by measuring a single sublattice (by using, e.g., two atom species). Remarkably, this protocol can prepare the 1D Greenberger-Horne-Zeilinger (GHZ) 'cat' state and 2D toric code with fidelity per site exceeding $0.9999$, and a 3D fracton state with fidelity $\gtrapprox 0.998$. In light of recent experiments showcasing 3D Rydberg atom arrays, this paves the way to the first experimental realization of fracton order. While the above examples are based on efficiently preparing and measuring cluster states, we also propose a multi-step procedure to create $S_3$ and $D_4$ non-Abelian topological order in Rydberg atom arrays and other quantum devices -- offering a route towards universal topological quantum computation.

Related papers

• Novel ground states and emergent quantum many-body scars in a two-species Rydberg atom array [9.501699961650854]
  Rydberg atom array has been established as one appealing platform for quantum simulation and quantum computation. Recent development of trapping and controlling two-species atoms using optical tweezer arrays has brought more complex interactions. We find some novel quantum states that cannot exist in traditional cold-atom platforms.
  arXiv  Detail & Related papers  (2024-08-28T17:36:10Z)
• Multipartite High-dimensional Quantum State Engineering via Discrete Time Quantum Walk [8.875659216970327]
  We give two schemes for the engineering task of arbitrary quantum state in $c$-partite $d$-dimensional system. A concrete example of preparing generalized Bell states is given to demonstrate the first scheme we proposed. We also show how these schemes can be used to reduce the cost of long-distance quantum communication.
  arXiv  Detail & Related papers  (2022-12-23T06:06:16Z)
• Coherent dynamics in a five-level atomic system [62.997667081978825]
  coherent control of multi-partite quantum systems is one of the central prerequisites in quantum information processing. Laser-cooled neon atoms in the metastable state of state $1s2 2s2 2p5 3s$ are prepared. Coherence properties of the prepared states are studied using Ramsey and spin echo measurements.
  arXiv  Detail & Related papers  (2022-10-21T11:44:15Z)
• Hierarchy of topological order from finite-depth unitaries, measurement and feedforward [0.0]
  Single-site measurements provide a loophole, allowing for finite-time state preparation in certain cases. We show how this observation imposes a complexity hierarchy on long-range entangled states based on the minimal number of measurement layers required to create the state, which we call "shots" This hierarchy paints a new picture of the landscape of long-range entangled states, with practical implications for quantum simulators.
  arXiv  Detail & Related papers  (2022-09-13T17:55:36Z)
• Efficient Bipartite Entanglement Detection Scheme with a Quantum Adversarial Solver [89.80359585967642]
  Proposal reformulates the bipartite entanglement detection as a two-player zero-sum game completed by parameterized quantum circuits. We experimentally implement our protocol on a linear optical network and exhibit its effectiveness to accomplish the bipartite entanglement detection for 5-qubit quantum pure states and 2-qubit quantum mixed states.
  arXiv  Detail & Related papers  (2022-03-15T09:46:45Z)
• Realization of arbitrary doubly-controlled quantum phase gates [62.997667081978825]
  We introduce a high-fidelity gate set inspired by a proposal for near-term quantum advantage in optimization problems. By orchestrating coherent, multi-level control over three transmon qutrits, we synthesize a family of deterministic, continuous-angle quantum phase gates acting in the natural three-qubit computational basis.
  arXiv  Detail & Related papers  (2021-08-03T17:49:09Z)
• Hardware-Efficient, Fault-Tolerant Quantum Computation with Rydberg Atoms [55.41644538483948]
  We provide the first complete characterization of sources of error in a neutral-atom quantum computer. We develop a novel and distinctly efficient method to address the most important errors associated with the decay of atomic qubits to states outside of the computational subspace. Our protocols can be implemented in the near-term using state-of-the-art neutral atom platforms with qubits encoded in both alkali and alkaline-earth atoms.
  arXiv  Detail & Related papers  (2021-05-27T23:29:53Z)
• Quantum optimization within lattice gauge theory model on a quantum simulator [7.48916170938768]
  Rydberg atom arrays constitute one of the most rapidly developing arenas for quantum simulation and quantum computing. SQA protocol can be realized easily on quantum simulation platforms such as Rydberg array D-wave annealer.
  arXiv  Detail & Related papers  (2021-05-15T04:14:38Z)
• Efficient Verification of Anticoncentrated Quantum States [0.38073142980733]
  I present a novel method for estimating the fidelity $F(mu,tau)$ between a preparable quantum state $mu$ and a classically specified target state $tau$. I also present a more sophisticated version of the method, which uses any efficiently preparable and well-characterized quantum state as an importance sampler.
  arXiv  Detail & Related papers  (2020-12-15T18:01:11Z)
• Preparation of excited states for nuclear dynamics on a quantum computer [117.44028458220427]
  We study two different methods to prepare excited states on a quantum computer. We benchmark these techniques on emulated and real quantum devices. These findings show that quantum techniques designed to achieve good scaling on fault tolerant devices might also provide practical benefits on devices with limited connectivity and gate fidelity.
  arXiv  Detail & Related papers  (2020-09-28T17:21:25Z)
• Quantum Gram-Schmidt Processes and Their Application to Efficient State Read-out for Quantum Algorithms [87.04438831673063]
  We present an efficient read-out protocol that yields the classical vector form of the generated state. Our protocol suits the case that the output state lies in the row space of the input matrix. One of our technical tools is an efficient quantum algorithm for performing the Gram-Schmidt orthonormal procedure.
  arXiv  Detail & Related papers  (2020-04-14T11:05:26Z)

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.