Quantum computing will revolutionize the digital world and researchers have unveiled an automated protocol-design approach that could unlock the computational power of quantum devices sooner than previously imagined.
In a research article in Intelligent Computing, three researchers from Chinese technology institutions outline a new method for achieving quantum computational advantage, something which represents a critical milestone in the development of quantum technologies.
This new approach maximizes the computational power of quantum computing without imposing new requirements on the quantum hardware and brings the advent of mainstream quantum computing much closer.
The abstract for the paper, How to Design a Classically Difficult Random Quantum Circuit for Quantum Computational Advantage Experiments, is below:
Quantum computational advantage is a critical milestone for near-term quantum technologies and a crucial step toward building practical quantum computers. Recent successful demonstrations of quantum computational advantage owe much to specially designed random quantum circuit (RQC) protocols that enable hardware-friendly implementation and, more importantly, pose great challenges for classical simulation. Here, we report an automated protocol-design approach for determining the optimal RQC in the Zuchongzhi quantum computational advantage experiment. Without a carefully designed protocol, the classical simulation cost of the Zuchongzhi 56-qubit 20-cycle RQC experiment would not be considerably higher than Google’s 53-qubit 20-cycle experiment, even though more qubits are involved. For Google’s latest RQC experiment using 70 qubits and 24 cycles, we estimate that the classical simulation cost can be increased by at least one order of magnitude using the proposed approach. The proposed method can be applied to generic planar quantum processor architectures and addresses realistic imperfections such as processor defects, underpinning quantum computational advantage experiments in future generations of quantum processors.
Quantum computing threats
As well as bringing potentially large benefits due to the huge increase in computing power it will bring, Quantum computing also poses unique threats and challenges.
These include:
- Cryptography and security: the most well-known threat is to current cryptographic standards. Quantum computers could potentially break widely used encryption protocols.
- Data privacy: given the potential to break current encryption standards, there is an associated risk to data privacy. Information that was encrypted and considered secure under current standards could be retroactively decrypted if adversaries are storing encrypted data today to decrypt it once quantum computers are sufficiently powerful.
- Digital signature forgery: quantum computing could compromise the integrity of digital signatures, which are crucial for verifying the authenticity of digital documents and software. This could undermine trust in digital transactions, software updates, and communications.
- Cyber security threats: beyond breaking cryptographic protocols, quantum computers could enable new types of cyber attacks that are not feasible today, exploiting quantum properties to find vulnerabilities in software and hardware that are considered secure by today’s standards.
