NMR techniques for quantum control and computation

Abstract

Fifty years of developments in nuclear magnetic resonance ͑NMR͒ have resulted in an unrivaled degree of control of the dynamics of coupled two-level quantum systems. This coherent control of nuclear spin dynamics has recently been taken to a new level, motivated by the interest in quantum information processing. NMR has been the workhorse for the experimental implementation of quantum protocols, allowing exquisite control of systems up to seven qubits in size. This article surveys and summarizes a broad variety of pulse control and tomographic techniques which have been developed for, and used in, NMR quantum computation. Many of these will be useful in other quantum systems now being considered for the implementation of quantum information processing tasks. CONTENTS

Spin properties of Hg1–xCdx Te/CdTe quantum wells

“…Also, the information on the spin surfaces may be employed in visualizing spin dynamics in spintronics devices and qubit evolution in quantum gates [20]. Of a particular interest may be needle-like spin surfaces, which can be matched by injector or collector spins having a specific polarization only.…”

Factorization of numbers with physical systems

“…The last years have witnessed enormous world-wide efforts in the quest of implementing quantum computation in various physical systems [Bou00] including nuclear magnetic resonance (NMR) [Van05], trapped atoms or ions [Cir95,Ste97,Lei03,Gul03,Roo04,Rie04,Tia05], cavity quantum electrodynamics [Rai01], and solid state systems like quantum dots [Ash96] and Josephson junctions [Mak01] in super conductors. Unfortunately, none of these settings satisfies the full set of DiVincenzo's criteria [USR04,EUR06].…”

Extremely Sub-Wavelength Negative Index Metamaterial

“…Extremely sub-wavelength metamaterials are also relevant to applications such as controlling spontaneous emission [27][28][29] and quantum information processing [30][31][32][33][34][35][36][37][38][39][40]. The light-matter interactions between free-space electromagnetic modes and quantum emitters are generally weak due to the small interaction cross-section of the latter.…”