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Recently, researchers from China reported significant progress on this front by developing a way to rapidly and reliably create large arrays of neutral atoms.

• Quantum computing – It is a technology that utilises the principles of quantum mechanics to solve complex problems much faster than traditional classical computers.
• It harnesses the unique behaviour of quantum physics, such as superposition, entanglement, and quantum interference and applies it to computing.
• Qubit – It is also known as quantum bits.
• It is the basic unit of information in quantum computing as bits plays in classical computing.
• Classical bits are binary and can hold only a position of 0 or 1, but qubits can have a superposition of all possible states.
• Building quantum computers – It requires assembling large array of qubits with no effect.
• Neutral atoms, like rubidium atoms, can be trapped and controlled by small laser beams called optical tweezers which serve as qubits in quantum computing.
• Arranging thousands of atoms accurately is crucial for performing complex operations and error corrections.
• Challenges in building – Perfectly placing atoms in large arrays is difficult because they are loaded randomly, often with missing sites.
• Assembling defect-free arrays involves moving atoms one by one or row by row, making the process slow and prone to errors.
• AI-based building – It quickly moves thousands of atoms at the same time, precisely controlling their positions and phases using laser holograms.
• AI use the Hungarian algorithm to find the ideal pairing of loaded atoms with a target position to organise them efficiently.
• It minimised the total distance of the atoms to move, also preventing any collisions during the rearrangement.
• Each movement of atoms was divided into 20 small steps to prevent heating and loss.
• It generated a hologram that simultaneously moved all atoms smoothly, precisely controlling their positions and light phases to avoid disturbances.

• Experimental AI model – Rearranging the atoms, whether 1000 or 10000, took the same time.
• The scientists assembled 2D arrays of up to 2,024 atoms free of any defects in about 60 milliseconds, substantially faster and more scalable.
• It is a convolutional neural network trained on simulated laser holograms, which quickly generates accurate holograms to guide atoms smoothly with minimal loss.
• The experiment used a high numerical aperture lens to tightly focus laser beams, acting like tweezers to trap and move atoms.
• A high-resolution camera captured the positions of the atoms and calculated their movements in real time.
• It created a cartoon-style animation of Schrödinger’s cat thought experiment by arranging 549 atoms within a 230 × 230 micrometre grid.
• Significance - It opens new paths toward building scalable quantum computers.

Reference

The Hindu| AI-Based Quantum Computing

Related News – National Quantum Mission