Quantum Computation and Information Seminar 

16/03/2012, 16:15 — 17:15 — Room P3.10, Mathematics Building
Francesco Ciccarello, Scuola Normale Superiore, Pisa

Deterministic realization of a universal quantum gate in a single scattering process

We show that a flying particle, such as an electron or a photon, scattering along a one-dimensional waveguide from a pair of static spin-1/2 centers, such as quantum dots or superconducting qubits, can implement a CZ gate (universal for quantum computation) between them. This occurs deterministically in a single scattering event, hence with no need for any post-selection or iteration, and without demanding the flying particle to bear any internal spin. We show that an easily matched hard-wall boundary condition along with the elastic nature of the process are key to such performances.