Quantum optimization

Simulated annealing (SA)

Quantum Monte Carlo (QMC)

Quantum approximated optimization algorithm (QAOA)

Adiabatic quantum computing (AQC)

Rydberg Maximum independent set (MIS) problem solver

Rydberg atom system intrinsically contains information about the solution of the MIS problem, one of the NP-complete optimization problems.

Maximum independent set (MIS) problem

Toward all-to-all connectivity

Rydberg blockade is distance dependent feature, so that the interaction is local. To generate controllable and all-to-all connected system, three auxiliary atom-assisted methods are proposed:

Parity architecture

Crossing gadget

Rydberg quantum wire

The optimization problem is mapped to the logical qubits, and these logical qubit space is embedded by physical qubits, which are supported by auxiliary atoms.

$$ \hat{H}{\rm logical}= \sum_j J_j \hat{\sigma}^z_j + \sum{(j,k)} J_{jk} \hat{\sigma}^z_j\hat{\sigma}^z_k \quad \rightarrow \quad\hat{H}_{\rm physical} $$

$$ \left| G(\hat{H}{\rm physical}) \right> \quad \rightarrow \quad\left| G(\hat{H}{\rm logical}) \right> $$