On balanced homodyne measurement -- simple proof of wave function collapse

Erwin Brüning; Shigeaki Nagamachi

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arXiv · 2404.12706

On balanced homodyne measurement -- simple proof of wave function collapse

Erwin Brüning·Shigeaki Nagamachi

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Abstract

Using only elementary calculus we prove that the balanced homodyne detector measures the quadrature phase amplitude of a signal. More precisely, after the measurement of photon numbers $l$, the collapse of the composite state of a strong laser beam and a signal approximates the collapse of the signal to the eigen-state of quadrature phase amplitude with eigen-value $r$.

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Erwin Brüning, Shigeaki Nagamachi. 2024-04-19. On balanced homodyne measurement -- simple proof of wave function collapse. https://arxiv.org/abs/2404.12706

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