Accelerating the exploration of quantum dynamics through ab initio anharmonic algorithms and tensor networks
Abstract
Many critical phenomena in physics, chemistry and biology, such as proton tunneling in enzyme catalysis and quantum coherence in photosynthesis, are governed by pronounced quantum behaviors. One of the main challenges is that the vibrational Hamiltonian is not known and the construction of the vibrational Hamiltonian requires performing computationally expensive electronic structure calculations. The second challenge is known as the "curse of dimensionality," that severely limits the size of the quantum systems that can be solved. Our group has been working on developing "Ab Initio Anharmonic Algorithms" (A3) to simulate and to gain further insight of vibrational coupling in the proton transfer processes. Our A3 codes work with Cartesian coordinates and make the construction of a kinetic energy operator (KEO) a trivial task. Furthermore, we have developed a set of codes to construct potential energy operators (PEO) with different resolutions that can balance computational costs and accuracy. Very recently, we are working to integrate A3 with Cytnx to transfer PEO into Matrix Product Operator (MPO) form and to use DMRG tools to solve time independent Schrödinger equations with up to 12 DoF of the central H3O+.
