Reversible computation is one of the most promising emerging technologies of the future. The usage of reversible circuits in computing devices can lead to a significantly lower power consumption. In this paper we study reversible logic circuits consisting of NOT, CNOT and 2-CNOT gates. We introduce a set F (n, q) of all transformations Zn2 → Z n 2 that can be implemented by reversible circuits ...

computer algorithms require an 'oracle' as an integral part. An oracle is a reversible quantum Boolean circuit, where the inputs are kept unchanged at the outputs and the functional outputs are realized along ancillary input constants (0 or 1). Recently, a nearest neighbour template based synthesis method of quantum Boolean circuits has been proposed to overcome the adjacency requirement of the...

We investigate anisotropic XXZ Heisenberg spin-1/2 chains with control fields acting on one of the end spins, with the aim of exploring local quantum control in arrays of interacting qubits. In this work, which uses a recent Lie-algebraic result on the local controllability of spin chains with “alwayson” interactions, we determine piecewise-constant control pulses corresponding to optimal fidel...

We show that if a language is recognized within certain error bounds by constantdepth quantum circuits over a nite family of gates, then it is computable in (classical) polynomial time. In particular, our results imply EQNC P; where EQNC is the constant-depth analogue of the class EQP. On the other hand, we adapt and extend ideas of DiVincenzo & Terhal [?] to show that, for any family F of quan...

Among the many proposals for the realization of a quantum computer, holonomic quantum computation is distinguished from the rest as it is geometrical in nature and thus expected to be robust against decoherence. Here we analyze the realization of various quantum gates by solving the inverse problem: Given a unitary matrix, we develop a formalism by which we find loops in the parameter space gen...

Recent investigations show that conservation laws limit the accuracy of gate operations in quantum computing. The inevitable error under the angular momentum conservation law has been evaluated so far for the CNOT, Hadamard, and NOT gates for spin 1/2 qubits, while the SWAP gate has no constraint. Here, we extend the above results to general single-qubit gates. We obtain an upper bound of the g...

We show that if a language is recognized within certain error bounds by constantdepth quantum circuits over a nite family of gates, then it is computable in (classical) polynomial time. In particular, our results imply EQNC P; where EQNC is the constant-depth analogue of the class EQP. On the other hand, we adapt and extend ideas of DiVincenzo & Terhal [?] to show that, for any family F of quan...

Seven all-optical logic gates based on hybrid plasmonic squared-shaped nanoring resonators and strips are proposed, designed, numerically analyzed using finite element method with COMSOL software package version 5.5. Constructive destructive interferences between the input port(s) control main operating principles used to produce proposed gates. The ratio of output optical power at a single por...

A classical logic gate connecting input and output light pulses is demonstrated. The gate operation is based on three steps: First, two incoming light pulses are stored in a Bose-Einstein condensate; second, atomic four-wave mixing generates a new matter wave; and third, the light pulses are retrieved. In the presence of the new matter wave, the retrieval generates a new optical wave. The latte...

Over the last few decades, research in reversible logic has increasingly become very popular and it is gaining greater momentum in the present word. Reversible logic has started finding concert applications in quantum computing, optical computing, nano-technology based system, low-power CMOS design, VLSI design. The principal objective of this work is to argue for quantum implementation of vari...