In a breakthrough towards scalable quantum computers, researchers from the Munich Quantum Valley, led by the Max Planck Institute of Quantum Optics, have successfully operated a register of 1200 neutral atoms continuously for over an hour. This achievement, published in a recent study, marks significant progress in scaling up quantum computing platforms with neutral atoms.
The team, led by Johannes Zeiher, research group leader and co-founder of the quantum computing start-up planqc, used a sophisticated technique to reload new atoms into the qubit register, allowing for indefinite operation. This innovation paves the way for large-scale quantum calculations, simulations, and measurements. The researchers are now working on controlling the electronic state of individual atoms in the register, enabling the generation of quantum entanglement, a crucial step towards practical quantum computing applications.
Scaling Up Quantum Computing: A Breakthrough in Neutral Atom Registers
Quantum computing has long been hailed as a revolutionary technology with the potential to solve complex problems that are currently unsolvable by classical computers. However, one of the major hurdles in the development of quantum computers is scaling up the number of qubits while maintaining control over individual constituents. Researchers from the Munich Quantum Valley (MQV) and the Max Planck Institute of Quantum Optics (MPQ), in collaboration with the quantum computing start-up planqc, have made a significant breakthrough in this area by successfully running a register of 1200 neutral atoms continuously for over an hour.
The team, led by Johannes Zeiher, research group leader at MPQ and co-founder of planqc, achieved this feat by using a sophisticated technique that allows them to successively reload new atoms into the qubit register. This innovation enables the operation of the quantum computer for an indefinite amount of time, overcoming the limitation of atomic losses that has plagued previous experiments.
The Challenge of Scaling Up Quantum Computers
The difficulty in calculating quantum systems with classical computers is well-documented. As the size of the system increases, its complexity grows exponentially, making it impossible to accurately calculate the behavior of even a hundred quantum particles using modern supercomputers. This limitation has led physicists to propose the use of quantum simulators and computers, which can circumvent these limitations by obeying the same laws as the systems being calculated.
While quantum simulators are primarily suited for specific problems in solid-state physics, quantum computers offer more universal applicability but require greater effort and control. They rely on individual, interconnected, and fully programmable storage units called qubits, which execute defined algorithms using quantum gates between them. The versatility and high processing power of quantum computers open up new scientific and technological possibilities, such as understanding complex materials and biomolecules.
Neutral Atoms: A Promising Approach to Scalable Quantum Computing
One approach to tackling the challenge of scaling up quantum computers is based on neutral atoms. Atomic quantum computers and simulators rely heavily on stable and scalable atomic arrangements, which form the registers required for computations. The atoms are trapped individually using optical tweezers or optical lattices, extremely precise periodic arrays formed from interfering laser beams. Each individual atom trapped in such tweezers or lattices can serve as a qubit.
However, as the register grows larger, more atoms are lost or heated, making the system prone to detrimental errors over time. In current systems, the entire register of atoms needs to be replenished regularly, severely limiting the size a system can attain.
The Reloading Technique: A Key Innovation
Johannes Zeiher and his team have now integrated a reloading zone into their experimental setup, which operates with the alkaline-earth atom strontium. Every 3.5 seconds, around 130 atoms are added to the register. This technique of replacing lost atoms in real-time is an important step towards the practical use of quantum technologies.
The next steps in this experiment involve controlling the electronic state of the atoms, for example with optical tweezers, so that each individual atom in the register becomes a qubit holding quantum information. Adding controlled interactions between nearby atoms in the array then enables the generation of quantum entanglement – the basis for any quantum computation.
The Future of Quantum Computing: Near-Term Applications and Industry Impact
The researchers are already working on concepts to combine their new technique with uninterrupted quantum computing. Maintaining the coherence of qubits during the reloading step is essential to unlock the great potential of quantum computing and simulation.
To execute a quantum algorithm with industry impact, thousands of qubits need to be operational for hours to run error-correction protocols. The results of this experiment could pave the way towards continuously maintaining such large arrays to explore near-term applications.
External Link: Click Here For More
