Molecular architectures based on pi-conjugated block copolymers for global quantum computation

TL;DR

This paper proposes a scalable, all-optical quantum computing scheme using pi-conjugated copolymer architectures, enabling controlled qubit interactions via a third energy state acting as a barrier.

Contribution

It introduces a novel molecular architecture for global quantum computation using electron-doped pi-conjugated copolymers with a unique barrier state for qubit control.

Findings

Estimated damping rate of 10^{-7} s suggests weak environmental coupling.

Proposes an all-optical, scalable quantum computing architecture.

Utilizes a third energy state as a barrier for entanglement control.

Abstract

We propose a molecular setup for the physical implementation of a barrier global quantum computation scheme based on the electron-doped pi-conjugated copolymer architecture of nine blocks PPP-PDA-PPP-PA-(CCH-acene)-PA-PPP-PDA-PPP (where each block is an oligomer). The physical carriers of information are electrons coupled through the Coulomb interaction, and the building block of the computing architecture is composed by three adjacent qubit systems in a quasi-linear arrangement, each of them allowing qubit storage, but with the central qubit exhibiting a third accessible state of electronic energy far away from that of the qubits' transition energy. The third state is reached from one of the computational states by means of an on-resonance coherent laser field, and acts as a barrier mechanism for the direct control of qubit entanglement. Initial estimations of the spontaneous emission decay rates associated to the energy level structure allow us to compute a damping rate of order 10^{-7} s, which suggest a not so strong coupling to the environment. Our results offer an all-optical, scalable, proposal for global quantum computing based on semiconducting pi-conjugated polymers.