IBM TJ Watson Research Center, Yorktown Heights, New York 10598, USA.
Phys Rev Lett. 2012 Aug 10;109(6):060501. doi: 10.1103/PhysRevLett.109.060501. Epub 2012 Aug 9.
We use quantum process tomography to characterize a full universal set of all-microwave gates on two superconducting single-frequency single-junction transmon qubits. All extracted gate fidelities, including those for Clifford group generators, single-qubit π/4 and π/8 rotations, and a two-qubit controlled-not, exceed 95% (98%), without (with) subtracting state preparation and measurement errors. Furthermore, we introduce a process map representation in the Pauli basis which is visually efficient and informative. This high-fidelity gate set serves as a critical building block towards scalable architectures of superconducting qubits for error correction schemes and pushes up on the known limits of quantum gate characterization.
我们使用量子过程层析成像技术来描述两个超导单频单结磁通量子比特上全微波门的完整通用集。所有提取的门保真度，包括 Clifford 群生成器、单量子比特 π/4 和 π/8 旋转以及两量子比特受控非门的保真度，都超过 95%（98%），而不（包括）减去态制备和测量误差。此外，我们在 Pauli 基中引入了一种过程映射表示，该表示直观有效且信息量丰富。这个高保真度的门集是超导量子比特纠错方案可扩展架构的关键构建块，并推动了量子门表征的已知极限。
