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Qubit gates using hyperbolic secant pulses



Hsiang S. Ku, Junling Long, Xian Wu, Mustafa Bal, Russell Lake, Edwin Barnes, Sophia Economou, David P. Pappas


It has been known since the early days of quantum mechanics that hyperbolic secant pulses possess the unique property that they can perform cyclic evolution on two-level quantum systems independently of the pulse detuning. More recently, it was realized that they induce detuning- controlled phases without changing state populations. Here, we experimentally demonstrate the properties of hyperbolic secant pulses on superconducting transmon qubits and contrast them with the more commonly used Gaussian and square waves. We further show that these properties can be exploited to implement phase gates, nominally without exiting the computational subspace. This enables us to demonstrate the first microwave-driven Z-gates with a single control parameter, the detuning.
Physical Review Letters


qubit, quantum mechanics, hyperbolic secant pulses, cyclic evolution, two-level quantum systems, pulse detuning, transmon qubits, Gaussian, square waves, computational subspace, microwave-driven Z-gates


Ku, H. , Long, J. , Wu, X. , Bal, M. , Lake, R. , Barnes, E. , Economou, S. and Pappas, D. (2017), Qubit gates using hyperbolic secant pulses, Physical Review Letters, [online], (Accessed April 18, 2024)
Created April 7, 2017, Updated June 26, 2020