Architectures for Quantum Simulation Showing a Quantum Speedup
Juan Bermejo-Vega, Dominik Hangleiter, Martin Schwarz, Robert Raussendorf, Jens Eisert · Physical Review X · 2018
One of the main aims in the field of quantum simulation is to achieve a quantum speedup, often referred to as "quantum computational supremacy," referring to the experimental realization of a quantum device that computationally outperforms classical computers.In this work, we show that one can devise versatile and feasible schemes of two-dimensional, dynamical, quantum simulators showing such a quantum speedup, building on intermediate problems involving nonadaptive, measurement-based, quantum computation.In each of the schemes, an initial product state is prepared, potentially involving an element of randomness as in disordered models, followed by a short-time evolution under a basic translationally invariant Hamiltonian with simple nearest-neighbor interactions and a mere sampling measurement in a fixed basis.The correctness of the final-state preparation in each scheme is fully efficiently certifiable.We discuss experimental necessities and possible physical architectures, inspired by platforms of cold atoms in optical lattices and a number of others, as well as specific assumptions that enter the complexity-theoretic arguments.This work shows that benchmark settings exhibiting a quantum speedup may require little control, in contrast to universal quantum computing.Thus, our proposal puts a convincing experimental demonstration of a quantum speedup within reach in the near term.