Recently, researchers at the Swiss Federal Institute of Technology (EPFL) in Lausanne have developed a technique for simultaneously reading multiple qubits, the smallest unit of quantum data. This research paves the way for a new generation of more powerful quantum computers.
"Right now, IBM and Google have the most powerful quantum computers in the world." Edoardo Charbon, director of EPFL's Advanced Quantum Structures (AQUA) laboratory, said. "IBM just launched a 127-qubit computer, Google's is 53 qubits."
But because of the limited number of qubits, engineers were unable to develop higher-performance computers. A team of EPFL engineers and British researchers have developed a new method that can break through technical barriers and read qubits more efficiently. This means that more qubits can be put into quantum computers. The findings were recently published in the journal Nature Electronics.
Quantum computers work differently from traditional computers. The former does not have a separate processor and memory chip, but is made up of qubits. Relying on the properties of quantum superposition and entanglement, quantum computers are able to perform complex calculations that can be applied to biochemistry, cryptography and other fields.
"The challenge we have now is to connect more qubits to computers — hundreds, if not thousands — to improve the processing power of computers," Charbon said, "and more complicatingly, the operating temperature of qubits is close to absolute zero (minus 273.15 degrees Celsius), so it's extremely difficult to read and control them at room temperature." Engineers typically use computers at room temperature, controlling each qubit individually. ”
A new method developed by lab staff Andrea Ruffino that can efficiently read 9 qubits simultaneously. This method can even be extended to larger qubit matrices. Although EPFL doesn't have a quantum computer, he integrates nanoscale semiconductor particles— quantum dots— into transistors to simulate qubits and conduct experiments under nearly identical conditions to quantum computers.
"My approach is based on the time and frequency of use." "The basic idea is to reduce the connection and operate three qubits with a single link," he said. ”
Lab director Charbon said this was "a real breakthrough": The new approach is feasible on integrated circuits of ordinary computer chips and at temperatures close to qubits, and in the future may lead to the integration of large qubit matrix systems with the necessary electrons, and the two technologies will work together simply and efficiently in a replicable way.