The new architecture with mobile atoms reduces the requirements for scale by 50 times.
Developers of quantum computers have long struggled with the same problem: to get one reliable logical qubit, you have to collect hundreds or thousands of physical. Now physicists have a way to drastically reduce this gap. A team from the California Institute of Technology, together with the startup Oratomic, has proposed an architecture that can reduce the requirements for the scale of quantum machines by an order of magnitude.
Calculations показываютshow that a full-fledged quantum computer with error correction can cost 10-20 thousand qubits. Previously, estimates reached millions. The difference is not cosmetic. With old approaches, the infrastructure itself became the main barrier: too many elements, too many mistakes, too complex assembly.
The booges are unstable in nature, so computing constantly has to be protected from failure. The classic scheme is built around redundancy: about a thousand physical quotes take one logical qubit. The new approach changes the logic of working redundancy and allows you to use the same resources more efficiently.
The authors rely on a platform with neutral atoms. In such a system, individual atoms play the role of qubits, and laser beams, the so-called optical tweezers, hold and move them in space. Unlike many other architectures, here you can not limit yourself to the nearest neighbors. Atoms can be moved over considerable distances inside the array and directly connected to each other.
Such flexibility opens up access to so-called highly effective error correction codes. One physical qubit in such a scheme can participate in several logical ones at once. As a result, one logical qubit can be collected from only five physical.
The approach is not only based on theory. Systems with neutral atoms evolve rapidly. The laboratories have already shown arrays of more than 6000 qubits. The new architecture uses exactly those properties of such systems that were previously considered just a convenient feature, and not a fundamental advantage.
The difference with the usual schemes can be seen at the level of interactions. In classical approaches, such as surface codes, qubits communicate mainly with the nearest neighbors. Such a topology limits the methods of information processing and complicates scaling. In arrays of neutral bond atoms, it is possible to build at great distances. This removes part of the restrictions and allows you to redistribute the load between qubits.
From a practical point of view, the work changes the assessment of the timing of the appearance of useful quantum machines. If the requirements for the number of qubits can really be reduced, the path from laboratory systems to working systems will significantly decrease. While we are talking about theoretical architecture, but it relies on existing experimental platforms, and not on hypothetical devices.
However, such progress has a downside. More compact and efficient quantum computers will get to tasks that are now considered difficult for classical machines. First of all, we are talking about cryptography. The Shore algorithm allows you to lay out large numbers into multipliers exponentially faster than classical methods, which means that it jeopardizes widely used circuits like RSA and cryptography on elliptical curves.
Developers of quantum computers have long struggled with the same problem: to get one reliable logical qubit, you have to collect hundreds or thousands of physical. Now physicists have a way to drastically reduce this gap. A team from the California Institute of Technology, together with the startup Oratomic, has proposed an architecture that can reduce the requirements for the scale of quantum machines by an order of magnitude.
Calculations показываютshow that a full-fledged quantum computer with error correction can cost 10-20 thousand qubits. Previously, estimates reached millions. The difference is not cosmetic. With old approaches, the infrastructure itself became the main barrier: too many elements, too many mistakes, too complex assembly.
The booges are unstable in nature, so computing constantly has to be protected from failure. The classic scheme is built around redundancy: about a thousand physical quotes take one logical qubit. The new approach changes the logic of working redundancy and allows you to use the same resources more efficiently.
The authors rely on a platform with neutral atoms. In such a system, individual atoms play the role of qubits, and laser beams, the so-called optical tweezers, hold and move them in space. Unlike many other architectures, here you can not limit yourself to the nearest neighbors. Atoms can be moved over considerable distances inside the array and directly connected to each other.
Such flexibility opens up access to so-called highly effective error correction codes. One physical qubit in such a scheme can participate in several logical ones at once. As a result, one logical qubit can be collected from only five physical.
The approach is not only based on theory. Systems with neutral atoms evolve rapidly. The laboratories have already shown arrays of more than 6000 qubits. The new architecture uses exactly those properties of such systems that were previously considered just a convenient feature, and not a fundamental advantage.
The difference with the usual schemes can be seen at the level of interactions. In classical approaches, such as surface codes, qubits communicate mainly with the nearest neighbors. Such a topology limits the methods of information processing and complicates scaling. In arrays of neutral bond atoms, it is possible to build at great distances. This removes part of the restrictions and allows you to redistribute the load between qubits.
From a practical point of view, the work changes the assessment of the timing of the appearance of useful quantum machines. If the requirements for the number of qubits can really be reduced, the path from laboratory systems to working systems will significantly decrease. While we are talking about theoretical architecture, but it relies on existing experimental platforms, and not on hypothetical devices.
However, such progress has a downside. More compact and efficient quantum computers will get to tasks that are now considered difficult for classical machines. First of all, we are talking about cryptography. The Shore algorithm allows you to lay out large numbers into multipliers exponentially faster than classical methods, which means that it jeopardizes widely used circuits like RSA and cryptography on elliptical curves.
