Superconducting and Silicon-Based Semiconductor Quantum Computers: A review

Quantum computers are based on the theory of quantum mechanics, and their powerful parallel data processing capability is expected to solve many mathematical problems that too are difficult to be handled by classical computers. Especially with the increase of data processing volume, the quantum advantage is more obvious. Among the many physical systems for quantum computers, superconducting quantum circuit and semiconductor quantum dot computers show amazing potential due to their compatibility with traditional integrated circuit process technology and ultrashort gating time of nanoseconds. Superconducting qubits consisting of Josephson junctions and superconducting coplanar capacitors are easily integrated into a large scale for their simple circuit structure and conventional semiconductor process compatibility. Semiconductor qubits made from isotopically purified silicon (Si)-based materials greatly suppress nuclear spin noise, and decoherence times of ultralong milliseconds can be achieved. In this article, we systematically describe the challenges faced by superconducting qubits and semiconductor qubits in hot issues such as error correction and decoherence and look into the future development of superconducting quantum computers and Si-based semiconductor quantum computers.