Hybrid RBRC seminar

Abstract: Experimental quantum platforms such as Rydberg atom arrays and trapped ions are generally limited to global driving by a single laser field, thus restricting the degree of individual control. Within this regime, three common approaches to local addressing are: (i) locally tunable laser phase, (ii) locally tunable Z rotations, and (iii) locally tunable laser intensity. Here, we consider the problem of realizing robust, arbitrary, site-dependent single-qubit unitaries in parallel under each of these three forms of individual control. For each case, we first give the shortest pulse sequence for parallel, arbitrary unitaries in the absence of error. In the presence of experimental imperfections, we further develop several classes of novel composite sequences for parallel, arbitrary unitaries robust against quasistatic errors in the amplitude and frequency of the driving field. When applicable, our pulse sequences yield higher-fidelity operations than existing composite pulse solutions such as BB1 or CORPSE at almost any level of error and decoherence, thus paving the way towards high-fidelity quantum information processing on noisy near-term systems with limited individual control.