Quantum Information Processing with Quantum Zeno Many-Body Dynamics

TL;DR

This paper demonstrates how the quantum Zeno effect can be used to control many-body quantum dynamics in a spin chain, enabling universal quantum computation with constant Hamiltonians.

Contribution

It introduces a method to implement quantum gates and state transfer using frequent measurements in a spin chain, advancing quantum information processing techniques.

Findings

Quantum Zeno effect enables control of many-body dynamics.

Implementation of universal quantum gates in a spin chain.

Potential for creating entangled pairs and single-qubit gates.

Abstract

We show how the quantum Zeno effect can be exploited to control quantum many-body dynamics for quantum information and computation purposes. In particular, we consider a one dimensional array of three level systems interacting via a nearest-neighbour interaction. By encoding the qubit on two levels and using simple projective frequent measurements yielding the quantum Zeno effect, we demonstrate how to implement a well defined quantum register, quantum state transfer on demand, universal two-qubit gates and two-qubit parity measurements. Thus, we argue that the main ingredients for universal quantum computation can be achieved in a spin chain with an always-on and constant many-body Hamiltonian. We also show some possible modifications of the initially assumed dynamics in order to create maximally entangled qubit pairs and single qubit gates.