A Priori Which-Way Information in Quantum Interference with Unstable Particles

Abstract

If an unstable particle used in a two-path interference experiment decays before reaching a detector, which-way information becomes available which reduces the detected interference fringe visibility $\mathcal{V}$. Here we argue that even when an unstable particle does {\em not} decay while in the interferometer, {\em a priori} which-way information is still available in the form of path predictability $\mathcal{P}$ which depends on the particle's decay rate $\Gamma$. We further demonstrate that in a matter-wave Mach-Zehnder interferometer using an excited atom with an appropriately tuned cavity, $\mathcal{P}$ is related to $\mathcal{V}$ through the duality relation ${\mathcal{P}}^2+{\mathcal{V}}^2=1$.

7 pages, 1 figure

References in corpus (10)

• Atom Interferometers
• Quantum interferometric visibility as a witness of general relativistic proper time
• Quantitative wave-particle duality and non-erasing quantum erasure
• Delayed-choice test of complementarity with single photons
• Quantitative complementarity in two-path interferometry
• Quantum mechanical which-way experiment with an internal degree of freedom
• Bohr's complementarity relation and the violation of the CP symmetry in high energy physics
• Testing the Equivalence Principle with Unstable Particles
• Mesoscopic interference
• Which-Way Information in Double-Slit and COW Experiments with Unstable Particles

Cited by in corpus (3)

• Weak Interaction Processes: Which Quantum Information is revealed?
• Effect of environment on the interferometry of clocks
• Quantum Path predictability for an electronic Mach-Zehnder interferometer in presence of environment induced Decoherence and Quantum Erasing process