Testing quantum mechanics with 16-microgram Schrödinger cat states

The superposition principle is one of the most fundamental principles of quantum mechanics. According to the Schrödinger equation, a physical system can be in any linear combination of its possible states.

Although the validity of this principle is routinely confirmed for microscopic systems, it remains unclear why macroscopic objects are not observed to be in superpositions of distinguishable states. Our experiments demonstrate the preparation of a mechanical resonator with an effective mass of 16 micrograms in nonclassical states of motion, such as Fock states and Schrödinger cat states. Furthermore, we investigate the decoherence dynamics of these states by observing the disappearance of Wigner negativities, which allows us to derive constraints on possible modifications to the Schrödinger equation. Our results have potential applications in continuous variable quantum information processing, quantum sensing, and in the fundamental investigation of quantum mechanics on massive systems.

References:

”Macroscopic Quantum Test with Bulk Acoustic Wave Resonators”
Björn Schrinski, Yu Yang, Uwe von Lüpke, Marius Bild, Yiwen Chu, Klaus Hornberger, Stefan Nimmrichter, and Matteo Fadel
Phys. Rev. Lett. 130, 133604 (2023)

“Schrödinger cat states of a 16-microgram mechanical oscillator”
Marius Bild, Matteo Fadel, Yu Yang, Uwe von Lüpke, Phillip Martin, Alessandro Bruno, and Yiwen Chu
Science 380, 274 (2023)