We compare the performance of the Quantum Approximate Optimization Algorithm (QAOA) with state-of-the-art classical solvers Gurobi and MQLib to solve the MaxCut problem on 3-regular graphs. We identify the minimum noiseless sampling frequency and depthp required for a quantum device to outperform classical algorithms. There is potential for quantum advantage on hundreds of qubits and moderate depth with a sampling frequency of 10 kHz. We observe, however, that classical heuristic solvers are capable of producing high-quality approximate solutions in linear time complexity. In order to match this quality for large graph sizesN , a quantum device must support depthp > 11. Additionally, multi-shot QAOA is not efficient on large graphs, indicating that QAOAp ≤ 11 does not scale withN . These results limit achieving quantum advantage for QAOA MaxCut on 3-regular graphs. Other problems, such as different graphs, weighted MaxCut, and 3-SAT, may be better suited for achieving quantum advantage on near-term quantum devices.
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Digital Tavis-Cummings Simulation on Superconducting Quantum Hardware with Error Mitigation
We explore digital quantum simulation of the dynamics of
- Award ID(s):
- 2047564
- PAR ID:
- 10481322
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- ISBN:
- 978-1-957171-27-2
- Page Range / eLocation ID:
- QM2A.3
- Format(s):
- Medium: X
- Location:
- Denver, Colorado
- Sponsoring Org:
- National Science Foundation
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Abstract Tavis-Cummings (TC) cavity quantum electrodynamical effects, describing the interaction of
N atoms with an optical resonator, are at the core of atomic, optical and solid state physics. The full numerical simulation of TC dynamics scales exponentially with the number of atoms. By restricting the open quantum system to a single excitation, typical of experimental realizations in quantum optics, we analytically solve the TC model with an arbitrary number of atoms with linear complexity. This solution allows us to devise the Quantum Mapping Algorithm of Resonator Interaction withN Atoms (Q-MARINA), an intuitive TC mapping to a quantum circuit with linear space and time scaling, whoseN +1 qubits represent atoms and a lossy cavity, while the dynamics is encoded through 2N entangling gates. Finally, we benchmark the robustness of the algorithm on a quantum simulator and superconducting quantum processors against the quantum master equation solution on a classical computer. -
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Abstract Optomechanical systems offer new opportunities in quantum information processing and quantum sensing. Many solid-state quantum devices operate at millikelvin temperatures—however, it has proven challenging to operate nanoscale optomechanical devices at these ultralow temperatures due to their limited thermal conductance and parasitic optical absorption. Here, we present a two-dimensional optomechanical crystal resonator capable of achieving large cooperativity
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