A robust system for Quantum Computation using Coherent Population Trap states of neutral atoms

TL;DR

This paper proposes a robust quantum computation system using neutral atoms in Coherent Population Trap states, enabling stable qubit manipulation and gate operations with minimal decoherence and perturbation.

Contribution

It introduces a novel scheme utilizing CPT states of neutral atoms for quantum computing, including state preparation and CNOT gate implementation.

Findings

CPT states can be used to encode qubits with minimal decoherence.

The system allows for the formation of superpositions and controlled gates.

Atoms in CPT states are immune to laser perturbations.

Abstract

A robust system for use of Quantum Computation using neutral atoms is presented in this communication. This scheme exploits a multilevel atomic system interacting with two lasers in such a way that it leads to formation of two Coherent Population Trap (CPT) states. The atomic population can be pumped alternatively between these two CPT states or any desired superposition of the two can also be formed. These two CPT states can then be mapped to two Qubits for Quantum Computation. Preparation of any desired state and formation of CNOT gates are explained below. A scheme for preparing 1-D lattice of mutually interacting spin systems, which mimic behaviour of magnetic spin systems is also shown. Atoms in CPT states do not interact with the lasers that prepare it and hence are free of perturbation. The states involved here are also made up of only ground states of bare atoms and hence are free of decoherence due to spontaneous emission. Thus, the configuration studied here is a good example of a very robust system.