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Operation Time of Quantum Gates

Lev B. Levitin·Tommaso Toffoli·Zachary Walton
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Abstract

We consider a quantum gate that complements the state of a qubit and then adds to it an arbitrary phase shift. It is shown that the minimum operation time of the gate is tau = (h/4E)(1+2 theta/pi), where h is Planck's constant, E is the quantum-mechanical average energy, and theta is the phase shift modulo pi. [We changed the name of a macro file to a more Windows-friendly one, and we clarified the remark "Note that..." after equation (4).]

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Lev B. Levitin, Tommaso Toffoli, Zachary Walton. 2002-10-25. Operation Time of Quantum Gates. https://arxiv.org/abs/quant-ph/0210076

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