Robust Quantum Search by Landau-Zener Stueckelberg Oscillations

  Yosi Atia  ,  Yonatan Oren  ,  Nadav Katz  
Hebrew University of Jerusalem, Israel

Quantum computation has three principle paradigms – the circuit model, the adiabatic model, and quantum walks. We present a new diabatic algorithm for the celebrated Grover search problem, exhibiting the same performance as the circuit model algorithm (Grover 96') and the adiabatic algorithm (Roland & Cerf 02'), while having a superior robustness to Hamiltonian control errors. Our novel algorithm is based on replacing the adiabatic Hamiltonian by Roland & Cerf by a periodic Hamiltonian, which rapidly oscillates between the initial and final Hamiltonian, effectively acting as a Landau-Zener-Stukelberg Hamiltonian. By abandoning the traditional adiabatic paradigm, we were able to induce coherent destruction of tunneling between the desired subspace of the computation and the orthogonal subspace, thus improving robustness and enabling near term experimental demonstration.