Quantum computing engineers from the University of New South Wales (UNSW) in Sydney have showcased an innovative approach to recording quantum information in silicon, presenting four unique ways of coding inside one atom. This breakthrough could simplify the design of flexible quantum chips and address challenges related to operating tens of millions of quantum computing units on a small area of silicon chips for quantum computers.
In their article, the engineers detailed how they utilized the 16 quantum states of antimony for coding quantum information. Antimony, a heavy atom that can be implanted into a silicon chip, was chosen because its core offers 8 different quantum states, along with an electron with 2 quantum states, resulting in a total of 16 quantum states within the same atom. To achieve the same number of states using simple quantum bits, 4 would need to be made and interconnected.
The researchers demonstrated the ability to control the electron and nucleus of antimony using magnetic and electric fields, as well as a combination of both fields. This opens up new possibilities for designing future quantum chips, providing engineers and physicists with greater flexibility in management techniques.
The different methods have distinct advantages: magnetic resonance offers higher speed compared to electric resonance, but its magnetic field may impact neighboring atoms. On the other hand, electric resonance is more localized, enabling the selection of a specific atom without influencing surrounding atoms.
Future quantum computers, capable of performing calculations and simulations that would surpass current supercomputers, are expected to include millions, if not billions, of quantum bits. The UNSW researchers are focusing on silicon, a technology well-established in traditional computer manufacturing, with the potential to accommodate millions of quantum bits per square millimeter of a chip.
The group’s next phase involves leveraging the expanded computing space of antimony to conduct more complex quantum operations, paving the way for the development of practical and commercially viable quantum equipment.