Jiang Zhang

Nonadiabatic holonomic quantum computation on coupled transmons with ancillary

  1. Tao Chen,
  2. Jiang Zhang,
  3. and Zheng-Yuan Xue
The physical implementation of holonomic quantum computation is challenging due to the needed complex controllable interactions on multilevel quantum systems. Here we propose to implement
the nonadiabatic holonomic quantum computation with the conventional capacitive coupled superconducting transmon qubits, where a universal set of quantum gates is constructed with the help of the interaction to an auxiliary qubit rather than consulting to delicate control over an auxiliary level of multilevel quantum systems. Explicitly, these quantum gates are realized by tunable interactions in an all-resonant way, which leads to high-fidelity gate operations. In this way, the distinct merit of our scheme is that we only use the two lowest levels of a transmon to form the qubit states. In addition, the auxiliary qubits are in their ground states before and after every gate operation. Therefore, our scheme paves a promising way towards the practical realization of high-fidelity nonadiabatic holonomic quantum computation.
arxiv pdf

Holonomic quantum computation in the ultrastrong-coupling regime of circuit QED

  1. Yimin Wang,
  2. Jiang Zhang,
  3. Chunfeng Wu,
  4. J. Q. You,
  5. and G. Romero
We present an experimentally feasible scheme to implement holonomic quantum computation in the ultrastrong-coupling regime of light-matter interaction. The large anharmonicity and the
Z2 symmetry of the quantum Rabi model allow us to build an effective three-level {\Lambda}-structured artificial atom for quantum computation. The proposed physical implementation includes two gradiometric flux qubits and two microwave resonators where single-qubit gates are realized by a two-tone driving on one physical qubit, and a two-qubit gate is achieved with a time-dependent coupling between the field quadratures of both resonators. Our work paves the way for scalable holonomic quantum computation in ultrastrongly coupled systems.
arxiv pdf