Lukas Sieberer

---

The computational superiority of a computer that operates according to the laws
of quantum mechanics relies crucially on quantum parallelism: different sets of
data stored as a superposition of quantum states can be processed in
parallel. To play out this advantage, however, one has to be able to prepare
such superpositions in the first place --- using only a minimum of computational
resources. We present a framework to efficiently prepare superpositions of
many-body spin configurations with programmable squared amplitudes. The spin
configurations are encoded in the degenerate ground states of the lattice-gauge
representation of an all-to-all connected Ising spin glass. The ground state
manifold is invariant under variations of the gauge degrees of freedom, which
take the form of four-body parity constraints. Our framework makes use of these
degrees of freedom by individually tuning them to dynamically prepare
programmable superpositions. The dynamics combines an adiabatic protocol with
controlled diabatic transitions.

---

University of Innsbruck
Seminar Room 0.03, ETP
Contact: Sebastian Diehl