Quantum computing with neutral atoms

Abstract

The manipulation of neutral atoms by light is at the heart of countless scientific discoveries in the field of quantum physics in the last three decades. The level of control that has been achieved at the single particle level within arrays of optical traps, while preserving the fundamental properties of quantum matter (coherence, entanglement, superposition), makes these technologies prime candidates to implement disruptive computation paradigms. In this paper, we review the main characteristics of these devices from atoms / qubits to application interfaces, and propose a classification of a wide variety of tasks that can already be addressed in a computationally efficient manner in the Noisy Intermediate Scale Quantum\cite{Preskill_NISQ} era we are in. We illustrate how applications ranging from optimization challenges to simulation of quantum systems can be explored either at the digital level (programming gate-based circuits) or at the analog level (programming Hamiltonian sequences). We give evidence of the intrinsic scalability of neutral atom quantum processors in the 100-1,000 qubits range and introduce prospects for universal fault tolerant quantum computing and applications beyond quantum computing.

Genome assembly using quantum and quantum-inspired annealing

“…While D-Wave machines use superconducting quantum circuits, setups based on ultracold Rydberg atom arrays 42 – 44 and trapped ions 45 , 46 can be also used for the efficient implementation of quantum annealing and other quantum optimization algorithms. Specifically, the system of Rydberg atom arrays has been studied in the context of solving the maximum independent set problem 43 , 44 , which is NP-hard. For longer sequences, as we have demonstrated, it is possible to use quantum-inspired algorithms that are capable of solving more complex problems using classical hardware.…”

Qualifying quantum approaches for hard industrial optimization problems. A case study in the field of smart-charging of electric vehicles

“…These results, obtained through a rigorous protocol, are very encouraging. Future works will involve testing the quantum approaches on the real Rydberg atoms quantum processor developed by Pasqal in the 100-1000 qubits range [16]; making the smart-charging problems more realistic by incorporating new constraints (e.g maximal available power on the load station), a real challenge as this should make the associated Hamiltonians to be implemented on the processor more complex; more specifically from an application viewpoint, looking for efficient heuristics to transform general graphs in unit-disk ones, which would drastically simplify the procedure for quantum solving of MIS. On this latter point, another interesting option is to explore smart-charging problems which are "naturally" two dimensional-e.g.…”

“…Moreover, improving these ratios is proved to be NP-Hard, unless some highly-believed conjectures of Complexity Theory would be false. In the case of Max-Cut, improving the approximation ratio from 0.878567 up to ( 16 17 = 0.941176) is NP-Hard [26] and thus out of reach of any polynomial classical algorithms unless P = NP, as it is to increase the ratio upon 1 -1/34k for Max-k-Cut [27]. Likewise, both problems are APX-Hard and thus, unless P = NP, they have no PTAS [24,28].…”

“…With a number of thousands of qubits of next generation neutral atom devices [16] in combination with the prospect of full parallelization of the parity encoding, Max-k-Cut represents a realistic application of near-term quantum devices.…”

“…In this framework, hardware and software are jointly developed in order to optimize the execution of the overall implementation. Among the variety of platforms that are currently being investigated, programmable arrays of single neutral atoms manipulated by light beams appear as a very powerful and scalable technology to manipulate up to a few thousands qubits [14][15][16]. For the problems under consideration, we provide some implementation details on such platform as developed and commercialized by the company Pasqal.…”