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 Physics , 1998, DOI: 10.1103/PhysRevB.58.11570 Abstract: We investigate numerically a single-pulse implementation of a quantum Control-Not (CN) gate for an ensemble of Ising spin systems at room temperature. For an ensemble of four-spin molecules'' we simulate the time-evolution of the density matrix, for both digital and superpositional initial conditions. Our numerical calculations confirm the feasibility of implementation of quantum CN gate in this system at finite temperature, using electromagnetic $\pi$-pulse.
 Physics , 2005, DOI: 10.1103/PhysRevA.72.032315 Abstract: Here we describe a simple mechanical procedure for compiling a quantum gate network into the natural gates (pulses and delays) for an Ising quantum computer. The aim is not necessarily to generate the most efficient pulse sequence, but rather to develop an efficient compilation algorithm that can be easily implemented in large spin systems. The key observation is that it is not always necessary to refocus all the undesired couplings in a spin system. Instead the coupling evolution can simply be tracked and then corrected at some later time. Although described within the language of NMR the algorithm is applicable to any design of quantum computer based on Ising couplings.
 Physics , 2012, Abstract: Spin currents in channels of a high mobility GaAs/AlGaAs two-dimensional electron gas are generated and detected using spin-polarized quantum point contacts. We have recently shown that the relaxation length of spin currents is resonantly suppressed when the frequency at which electrons bounce between channel walls matches the Larmor frequency. Here we demonstrate that a gate on top of the channel tunes such ballistic spin resonance by tuning the velocity of electrons and hence the bouncing frequency. These findings demonstrate a new mechanism for electrical control of spin logic circuits.
 中国物理 B , 2007, Abstract: We present a systematic simple method to implement a generalized quantum control-NOT (CNOT) gate on two $d$-dimensional distributed systems. First, we show how the nonlocal generalized quantum CNOT gate can be implemented with unity fidelity and unity probability by using a maximally entangled pair of qudits as a quantum channel. We also put forward a scheme for probabilistically implementing the nonlocal operation with unity fidelity by employing a partially entangled qudit pair as a quantum channel. Analysis of the scheme indicates that the use of partially entangled quantum channel for implementing the nonlocal generalized quantum CNOT gate leads to the problem of `the general optimal information extraction'. We also point out that the nonlocal generalized quantum CNOT gate can be used in the entanglement swapping between particles belonging to distant users in a communication network and distributed quantum computer.