Fast and robust quantum control based on Pauli blocking
Tom Dowdall (1), Albert Benseny (2), Thomas Busch (2), and Andreas Ruschhaupt(1)
(1 University College Cork, 2 Okinawa Institute of Science and Technology Graduate University)
Coherent quantum control over many-particle quantum systems requires high fidelity dynamics. One way of achieving this is to use adiabatic schemes where the system follows an instantaneous eigenstate of the Hamiltonian over timescales that do not allow transitions to other states. This, however, makes control dynamics very slow. Here we introduce another concept that takes advantage of preventing unwanted transitions in fermionic systems by using Pauli blocking: excitations from a protected ground state to higher-lying states are avoided by adding a layer of {\it buffer} fermions, such that the {\it protected} fermions cannot make a transition to higher lying excited states because these are already occupied. This allows the speed-up adiabatic evolutions of the system. We do a thorough investigation of the technique, and demonstrate its power by applying it to high fidelity expansion and other tasks in ultracold atoms systems in anharmonic traps.
Ref.: Phys. Rev. A 96, 043601 (2017)