Ian R. Petersen

Robust manipulation of superconducting qubits in the presence of fluctuations

  1. Daoyi Dong,
  2. Chunlin Chen,
  3. Bo Qi,
  4. Ian R. Petersen,
  5. and Franco Nori
Superconducting quantum systems are promising candidates for quantum information processing due to their scalability and design flexibility. However, the existence of defects, fluctuations,
and inaccuracies is unavoidable for practical superconducting quantum circuits. In this paper, a sampling-based learning control (SLC) method is used to guide the design of control fields for manipulating superconducting quantum systems. Numerical results for one-qubit systems and coupled two-qubit systems show that the „smart“ fields learned using the SLC method can achieve robust manipulation of superconducting qubits even in the presence of large fluctuations and inaccuracies.
arxiv pdf

Quantum Robust Stability of a Small Josephson Junction in a Resonant Cavity

  1. Ian R. Petersen
This paper applies recent results on the robust stability of nonlinear quantum systems to the case of a Josephson junction in a resonant cavity. The Josephson junction is characterized
by a Hamiltonian operator which contains a non-quadratic term involving a cosine function. This leads to a sector bounded nonlinearity which enables the previously developed theory to be applied to this system in order to analyze its stability.
arxiv pdf