Two-qubit logical gates are proposed on the basis of two atoms trapped in a cavity setup and commonly addressed by laser fields. Losses in the interaction by spontaneous transitions are efficiently suppressed by employing adiabatic transitions and the quantum Zeno effect. Dynamical and geometrical conditional phase gates are suggested. This method provides fidelity and a success rate of its gates very close to unity. Hence, it is suitable for performing quantum computation.

arXiv:quant-ph/0111088Physical Review LettersOct 14, 2002214 citations

Robust and fast geometric quantum computation with multiqubit gates in cavity QED

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Physical Review AJun 9, 200923 citations

Physical Review B

Simple quantum logic gate with quantum dot cavity QED systems

Thaddeus D. Ladd, Y. Yamamoto

Published Dec 6, 2011• 23 citations

Publisher

Abstract

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planar cavity, employs only a single laser pulse, and allows the integration of many entangled qubits on one semiconductor chip. We present the gate in the contexts of both adiabatic evolution and geometric phases, and calculate the degradation of performance in the presence of both spontaneous emission and cavity loss.

DOI: 10.1103/physrevb.84.235307

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A scheme is proposed for realizing geometric quantum computation with one-qubit unitary gates and

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-qubit $(N\ensuremath{\ge}2)$ phase gates in cavity QED. In the scheme, the cavity field and excited states are virtually excited by controlling appropriately atom-field couplings and engineering adiabatic passage; thus the gate operations are insensitive to the cavity decay and the atomic spontaneous emission. Furthermore, the

N

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