Molecular topological quantum computer

Abstract

Biomolecular residue pairs have been utilized in constructing quantum logic gates (QLGs), significantly reducing the hardware size to the subnanoscale level. However, the development of molecular fault-tolerant topological quantum computers (TQCs) presents challenges in error reduction and hardware size minimization. This study presents the manipulation of molecular QLGs (MQLGs) by utilizing protein residue pairs as molecular transistors, enabling the construction of molecular topological QLGs. This innovative approach leverages molecular functionality in quantum computer (QC) designs to build sub-nanometer transistors that significantly reduce size, enhance efficiency, and accelerate computing. The transmission spectra of electron transfer in molecular junction systems were analyzed using the non-equilibrium Green’s function method. The molecular field effect led to the observation of four quantum states on a two-dimensional potential energy surface with two degrees of freedom—proton translation and molecular rotation. These states form a quaternary QLG, similar to a 2-qubit controlled-NOT logic gate. By applying the Kitaev honeycomb lattice model, MQLGs were employed to generate nonabelian anyons that adhere to fusion rules, such as Ising and Fibonacci anyons. Furthermore, quantum circuits incorporating nonabelian anyons and their fusion processes were developed for practical applications. These findings underscore the shift away from conventional atom-based silicon technology and highlight the potential for innovative applications of molecular universal QLGs, particularly in the advancement of sub-nanometer molecular fault-tolerance TQCs.