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arXiv · 1604.07692

Evading Vacuum Noise: Wigner Projections or Husimi Samples?

Christian R. Müller·Christian Peuntinger·Thomas Dirmeier·Imran Khan·Ulrich Vogl·Christoph Marquardt·Gerd Leuchs·Luis L. Sánchez-Soto·Yong Siah Teo·Zdenek Hradil·Jaroslav Řeháček
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Abstract

The accuracy in determining the quantum state of a system depends on the type of measurement performed. Homodyne and heterodyne detection are the two main schemes in continuous-variable quantum information. The former leads to a direct reconstruction of the Wigner function of the state, whereas the latter samples its Husimi $Q$~function. We experimentally demonstrate that heterodyne detection outperforms homodyne detection for almost all Gaussian states, the details of which depend on the squeezing strength and thermal noise.

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Christian R. Müller, Christian Peuntinger, Thomas Dirmeier, Imran Khan, Ulrich Vogl, Christoph Marquardt, Gerd Leuchs, Luis L. Sánchez-Soto, Yong Siah Teo, Zdenek Hradil, Jaroslav Řeháček. 2016-04-26. Evading Vacuum Noise: Wigner Projections or Husimi Samples?. https://doi.org/10.1103/physrevlett.117.070801

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