Synthetic quantum systems help solve complex real-world applications

Article by: Maurizio Di Paolo Emilio

Simulation using synthetic quantum systems is a potential tool for solving difficult NP-Hard (non-deterministic polynomial time hardness) problems, which is a task where traditional numerical approaches frequently fail. Pasqal, a French company founded in 2019 by five scientists — Christophe Jurczak, Alain Aspect, Antoine Browaeys, Thierry Lahaye and CEO Georges-Olivier Reymond — is developing a quantum processing unit (QPU) particularly suited to simulation. Pasqal also announced a collaboration with Nvidia to create a Center of Excellence in Quantum Computing, comprising a cluster of 10 Nvidia DGX A100 systems with Nvidia InfiniBand networking to enhance its portfolio of solutions. In addition, they received the 2021 Start-Up of the Year from Usine Nouvelle at the Assises de l’Industrie in Paris, which focused on the theme “Reconstructing French industry”.

Intelligent electric vehicle charging, grid design, grid management, grid reliability, and process innovation are just some of the issues that can be successfully addressed. Today, quantum processors can be built on a variety of platforms, including trapped ions, superconducting circuits, quantum dots and neutral atoms. Whichever method is used, designers must overcome two major hurdles: increasing the size of the assembly while maintaining high quality control over parameters, and verifying the outputs of these complex and exceptional systems. The topologies of neutral atom devices are unique in many ways, not only compared to conventional devices in general, but also compared to quantum analogues. Compared to other quantum devices, platforms of neutral atoms, for example, can easily achieve quantum registers with higher number of qubits and higher connectivity.

Pasqal QPU

Quantum Simulation is the most promising use of Pasqal’s QPU, in which the quantum processor is used to obtain knowledge about a quantum system of interest. It seems reasonable to use a quantum system as a computational resource for quantum problems, as Richard Feynman pointed out in the 20th century. Neutral atom quantum processors will facilitate pure scientific discovery, and there are several areas of application at the industrial level, such as the creation of new materials for energy storage and transport, or chemical calculations for drug development. .

“At Pasqal, we are not just scientists, we are not just academics, we are industrializing our technology. By working with quantum technology, we want to build and sell a product that is reliable and helps solve complex industrial problems in many contexts, ”said Reymond.

Among Pasqal’s customers is EDF, the French electricity company. In the energy sector, Pasqal is working with EDF to develop innovative smart mobility solutions (see Figure 1). We can think, for example, of a city with a large number of electric vehicles (like a fleet) that must be recharged at the end of each day. Of course, this is a complex problem since it is necessary to schedule recharging and manage the future need for electrical energy. According to Pasqal, the solution to this problem, also known as smart charging, cannot be found with conventional computers, especially when it evolves. However, this problem can be solved with the help of a quantum processor.

“We are building a quantum processor based on neutral atom technology. Our qubits are atoms. This means that we manipulate atoms one by one to store and encode quantum information, ”said Georges-Olivier Reymond.

Recent breakthroughs have allowed us to reach unprecedented system sizes, with quantum registers containing more than 190 atoms. This large number of interacting quantum particles makes it possible to simulate the dynamics of a quantum system with several bodies well beyond the capabilities of current classical approaches.

According to Pasqal, this approach offers many advantages. First, the installation can operate at room temperature and does not need to be cooled. Second, all the elements are structurally the same, since they are built by nature. Third, the quantum computers developed by Pasqal consume very little power, as much as four hairdryers. Finally, Pasqal’s qubits can be controlled using light, a very powerful tool that can be adapted to almost any need.

To do this, Pasqal uses a single laser which is then split into multiple laser beams. This means that this solution is highly scalable as it allows the control of hundreds of qubits. As some peer-reviewed articles prove, this technology is already capable of controlling up to 200 qubits. Figure 2 shows an array of atoms filled with 14 x 14, corresponding to 196 qubits.

“The quality of the quantum operation is directly linked to the quality of the laser beam, in terms of frequency stabilization for example. We use the best laser in our class and we also implement stabilization techniques to ensure this high efficiency of the quantum operation, ”said Reymond.

Pasqal said its processors can already solve serious computational problems that are inefficient for traditional computers, in addition to simulating scientific processes. The native resolution of a well-known graph problem, the Maximum Independent Set (MIS), is a good illustration of this. As the size of the graph increases, this problem, which has immediate applications in network design and finance, becomes difficult to solve on a traditional computer. A set of interacting cold neutral atoms can be used as a quantum resource to solve the MIS problem, each atom representing a vertex of the considered graph.

Besides smart charging, there are other energy related issues such as wind farms that can be solved efficiently through simulation run on a quantum processor. The problem statement could be: how to simulate and optimize the production efficiency of a wind farm under different wind conditions, number of wind turbines and different configurations?

“Having these atoms simulating a wind farm is absolutely unexpected. We believe that the energy sector is the one that will be impacted the most by quantum technology, ”said Reymond.

Pasqal is in the process of assembling its first 200-qubit computer, but the company knows that is probably not enough to achieve an industrial quantum advantage. At Pasqal, scientists believe they will need to reach 1,000 qubits to deliver this kind of performance, so they are working to increase the number of qubits as part of the company’s roadmap.

“It’s a big challenge, but we’re on track to deliver 1,000 qubits by 2023 using a single processor. What customers also ask us for is support training and applications. This is because it is a new technology and they need to be supported throughout this quantum journey. We provide them with a turnkey solution, the hardware with the complete solutions and, in addition, the applications, ”said Reymond.

This article was originally published on EE time.

Maurizio Di Paolo Emilio holds a doctorate in physics and is a telecommunications engineer and journalist. He has worked on various international projects in the field of gravitational wave research. It collaborates with research institutes to design data acquisition and control systems for space applications. He is the author of several books published by Springer, as well as numerous scientific and technical publications on electronic design.