In recent years, quantum computers have captivated the world with their extraordinary potential. Industry giants like IBM and Google have been racing to build increasingly powerful quantum machines, with the expectation that they will revolutionize fields ranging from encryption to medical research. At the heart of these quantum machines are qubits, the quantum counterparts of classical bits, capable of existing in a superposition of both 1 and 0 simultaneously.
However, a significant stumbling block in the path of quantum computing progress is the phenomenon known as ‘quantum error.’ Even the most powerful quantum computers today suffer from inefficiencies, with more than 1,000 qubits affected by errors for every single unaffected ‘logical’ qubit.
The ‘Cat State’ Qubit Revolution
Enter the innovative French startup, Alice & Bob, which is pioneering a new kind of qubit designed to conquer the quantum error challenge. Their approach draws inspiration from Schrödinger’s Cat experiment, a foundational concept in quantum mechanics that explores the notion of quantum superposition.
Rather than encoding qubits using varying energy levels, Alice & Bob have devised a strategy based on establishing two diametrically opposed states—akin to the famous life-or-death state of Schrödinger’s Cat. They’ve achieved this by utilizing superconducting microwave resonators that oscillate between two distinct states.
The researchers believe that breaking RSA-2048 encryption using a traditional quantum computer would require approximately 22 million normal qubits, whereas their ‘cat state’ qubits would reduce the requirement to just 350,000. Furthermore, for each logical qubit, Alice & Bob’s technology would need only 40 qubits.
Amazon’s Interest and External Validation
The potential of these ‘cat state’ qubits has garnered significant attention, even from industry behemoth Amazon, which has embarked on its own ‘cat state’ qubit research. While the startup initially felt the pressure of competing with Amazon, they recognized it as external validation.
Alice & Bob’s ‘cat states’ exhibit remarkable resistance to bit flips, where a qubit’s state flips from 1 to 0 or vice versa. Although they are somewhat more susceptible to phase flips, in which qubits shift between opposing phases, the researchers have emphasized that resolving one type of error is more manageable than dealing with both.
Future Ambitions
Looking ahead, Alice & Bob have ambitious plans. They aim to create a 14-qubit system by the end of 2023, with an additional six months needed for calibration. Their groundbreaking work in ‘cat state’ qubits holds promise not only for quantum computing but also for the realm of encryption and beyond. Stay tuned for further developments from this pioneering startup as they push the boundaries of quantum technology.
