  With the current progress of quantum computing, quantum annealing is being
introduced as a powerful method to solve hard computational problems. In this
paper, we study the potential capability of quantum annealing in solving the
phase unwrapping problem, an instance of hard computational problems. To solve
the phase unwrapping problem using quantum annealing, we deploy the D-Wave
Advantage machine which is currently the largest available quantum annealer.
The structure of this machine, however, is not compatible with our problem
graph structure. Consequently, the problem graph needs to be mapped onto the
target (Pegasus) graph, and this embedding significantly affects the quality of
the results. Based on our experiment and also D-Wave's reports, the lower chain
lengths can result in a better performance of quantum annealing. In this paper,
we propose a new embedding algorithm that has the lowest possible chain length
for embedding the graph of the phase unwrapping problem onto the Pegasus graph.
The obtained results using this embedding strongly outperform the results of
Auto-embedding provided by D-Wave. Besides the phase unwrapping problem, this
embedding can be used to embed any subset of our problem graph to the Pegasus
graph.
