J. P. Barjaktarevic | Searcharxiv

arXiv2005

Measurement-Based Teleportation Along Quantum Spin Chains

We consider teleportation of an arbitrary spin-1/2 target quantum state along the ground state of a quantum spin chain. We present a decomposition of the Hilbert space of the many body quantum state into 4 vector spaces. Within each of these subspaces, it is possible to take any superposition of states, and use projective measurements to perform unit fidelity teleportation. Any such superposition is necessarily a spin liquid state. We also show that all total spin-0 quantum states belong in the same space, so that it is possible to perform unit fidelity teleportation over any one-dimensional spin-0 many body quantum state. We generalise to $n$-Bell states, and present some general bounds on fidelity of teleportation given a general state of a quantum spin chain.

quant-ph↗

arXiv2004

Fast simulation of a quantum phase transition in an ion-trap realisable unitary map

We demonstrate a method of exploring the quantum critical point of the Ising universality class using unitary maps that have recently been demonstrated in ion trap quantum gates. We reverse the idea with which Feynman conceived quantum computing, and ask whether a realisable simulation corresponds to a physical system. We proceed to show that a specific simulation (a unitary map) is physically equivalent to a Hamiltonian that belongs to the same universality class as the transverse Ising Hamiltonian. We present experimental signatures, and numerical simulation for these in the six-qubit case.

quant-ph↗