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arXiv · 0812.1626

Generating "squeezed" superpositions of coherent states using photon addition and subtraction

P. Marek·H. Jeong·M. S. Kim
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Abstract

We study how photon addition and subtraction can be used to generate squeezed superpositions of coherent states in free-traveling fields (SSCSs) with high fidelities and large amplitudes. It is shown that an arbitrary $N$-photon subtraction results in the generation of a SSCS with nearly the perfect fidelity ($F>0.999$) regardless of the number of photons subtracted. In this case, the amplitude of the SSCS increases as the number of the subtracted photons gets larger. For example, two-photon subtraction from a squeezed vacuum state of 6.1dB can generate a SSCS of $α=1.26$, while in the case of the four-photon subtraction a SSCS of a larger amplitude $α=1.65$ is obtained under the same condition. When a photon is subtracted from a squeezed vacuum state and another photon is added subsequently, a SSCS with a lower fidelity ($F\approx 0.96$) yet higher amplitude ($α\approx2$) can be generated. We analyze some experimental imperfections including inefficiency of the detector used for the photon subtraction.

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P. Marek, H. Jeong, M. S. Kim. 2008-12-09. Generating "squeezed" superpositions of coherent states using photon addition and subtraction. https://doi.org/10.1103/physreva.78.063811

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