Suppressing the entanglement growth in matrix product state evolution of quantum systems through nonunitary similarity transformations

In strong-coupling regimes, quantum dynamical effects can alter conventional physics described by perturbation theories, but the simulations of these systems using matrix product states---such as multilevel vibronic that are relevant to energy and electron transfer reactions---suffer from rapid entanglement growth during their real-time evolution, impeding explorations spectra, dynamics, kinetics. We examine possibility nonunitary transformations in matrix-product-state systems, spin-boson model showcase reduced entanglement. By appropriately choosing transformation, rate is suppressed, improving efficiency simulations. Entanglement control achieved transformation-induced biased transitions among system states, ``projecting'' (approximately) state one eigenstates system-bath coupling operator, thus controlling exchange between bath. The transformation be applied many-body including spin chains systems; approach improves numerical