Time-optimal unitary operations in Ising chains: Unequal couplings and fixed fidelity

Alberto Carlini, Tatsuhiko Koike

研究成果: Article査読

19 被引用数 (Scopus)


We analytically determine the minimal time and the optimal control laws required for the realization, up to an assigned fidelity and with a fixed energy available, of entangling quantum gates (CNOT) between indirectly coupled qubits of a trilinear Ising chain. The control is coherent and open loop, and it is represented by a local and continuous magnetic field acting on the intermediate qubit. The time cost of this local quantum operation is not restricted to be zero. When the matching with the target gate is perfect (fidelity equal to 1), we provide exact solutions for the case of equal Ising coupling. For the more general case when some error is tolerated (fidelity smaller than 1), we give perturbative solutions for unequal couplings. Comparison with previous numerical solutions for the minimal time to generate the same gates with the same Ising Hamiltonian but with instantaneous local controls shows that the latter are not time optimal.

ジャーナルJournal of Physics A: Mathematical and Theoretical
出版ステータスPublished - 2013 2月 1

ASJC Scopus subject areas

  • 統計物理学および非線形物理学
  • 統計学および確率
  • モデリングとシミュレーション
  • 数理物理学
  • 物理学および天文学(全般)


「Time-optimal unitary operations in Ising chains: Unequal couplings and fixed fidelity」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。