  Density matrix embedding theory (DMET) is a quantum embedding theory for
strongly correlated systems. From a computational perspective, one bottleneck
in DMET is the optimization of the correlation potential to achieve
self-consistency, especially for heterogeneous systems of large size. We
propose a new method, called projected density matrix embedding theory
(p-DMET), which achieves self-consistency without needing to optimize a
correlation potential. We demonstrate the performance of p-DMET on the
two-dimensional Hubbard model.
