摘要
To utilize higher-dimensional quantum systems, in this Letter we derive a generalized cross-resonance scheme for realizing maximally entangling two-qutrit gates on fixed-frequency transmons beyond the 0-1 subspace. Our two-qutrit gates, namely, U01CR and U12CR, acting on the 0-1 and 1-2 energy transitions of transmons, respectively, directly allow for entanglement on the 1-2 levels. Unlike the known works, our gate is parametric in nature, enabling us to construct multiple entangling gates of interest. By performing simulations in Qiskit, we demonstrate two-qutrit generalized controlled-X (U01CX and U12CX) and controlledCH and U12CH) gates, which are instances of the proposed UCR gates, with reported gate fidelities of 93.17% (99.73%), 91.47% (97.88%), 96.06% (99.39%), and 95.68% (98.99%), respectively, with (and without) noise. We also reveal a two-qutrit Bell state with a fidelity of 87.54% (99.06%), with a complete Bell state preparation in an similar to 514 ns pulse sequence, which is less than the gate time of the known scheme by cross-Kerr-based entangling gates.