How to extend quantum experiments

Abstract

Key words Foundations of quantum physics, wave-particle duality, quantum entanglement, mesoscopic quantum physics, quantum-classical transition. PACS 03.65.-w, 03.65.Ta, 03.65.Ud, 03.65.Yz, 03.67.-a, 03.67.Mn This paper is dedicated to Prof. Paolo Tombesi on the occasion of his 70th birthday.Modern experimental developments allow to address the fundamental challenges of quantum physics on new, macroscopic scales. How far can such experiments be pushed with current technology? We discuss three specific examples, long-distance photonic entanglement, matter wave interferometry and superposition states of mechanical resonators, and discuss possible extensions to these experiments. It turns out that there is "plenty of room at the top" for macroscopic quantum experiments, even with presently available technology.

Quantum optomechanics—throwing a glance [Invited]

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Cavity optoelectromechanical regenerative amplification

“…Cavity optomechanical systems have many promising applications, such as on-chip phononic information processing [8,9], displacement sensing at the standard quantum limit [10,11], and ultrasensitive force measurement [12]. Ground-state cooled optomechanical oscillators are also proposed to probe exotic problems such as macroscopic quantum behavior [13], quantum gravity [14] and microscale gravity [15].…”

Large scale EPR correlations and cosmic gravitational waves

“…Up to now, the reported limits are associated with practical rather than fundamental issues. Efforts are going on for mastering these technical limitations and approaching closer and closer the underlying fundamental questions in future experiments [11,14].…”