Quantum Communication through Spin Chain Dynamics: an Introductory Overview

Abstract

We present an introductory overview of the use of spin chains as quantum wires, which has recently developed into a topic of lively interest. The principal motivation is in connecting quantum registers without resorting to optics. A spin chain is a permanently coupled 1D system of spins. When one places a quantum state on one end of it, the state will be dynamically transmitted to the other end with some efficiency if the spins are coupled by an exchange interaction. No external modulations or measurements on the body of the chain, except perhaps at the very ends, is required for this purpose. For the simplest (uniformly coupled) chain and the simplest encoding (single qubit encoding), however, dispersion reduces the quality of transfer. We present a variety of alternatives proposed by various groups to achieve perfect quantum state transfer through spin chains. We conclude with a brief discussion of the various directions in which the topic is developing.

Material covered till Dec 2006

References in corpus (16)

• Perfect Transfer of Arbitrary States in Quantum Spin Networks
• Diverging Entanglement Length in Gapped Quantum Spin Systems
• Mirror Inversion of Quantum States in Linear Registers
• The Propagation of Quantum Information Through a Spin System
• Spin Chains as Perfect Quantum State Mirrors
• Perfect quantum state transfer with randomly coupled quantum chains
• Perfect State Transfer: Beyond Nearest-Neighbor Couplings
• Quantum state transmission via a spin ladder as a robust data bus
• From perfect to fractal transmission in spin chains
• Improved transfer of quantum information using a local memory
• Quantum information transport to multiple receivers
• Geometric Effects and Computation in Spin Networks
• Cloning transformations in spin networks without external control
• Mesoscopic continuous and discrete channels for quantum information transfer
• Engineering massive quantum memories by topologically time-modulated spin rings
• Entanglement creation and distribution on a graph of exchange-coupled qutrits

Cited by in corpus (4)

• Theory of ground state factorization in quantum cooperative systems
• Entanglement purification without controlled-NOT gates by using the natural dynamics of spin chains
• Spin chain model for correlated quantum channels
• The characteristic polynomial of the next-nearest-neighbour qubit chain for single excitations