Spin-Dependent Force and Inverted Harmonic Potential for Rapid Creation of Macroscopic Quantum Superpositions

TL;DR

This paper combines spin-dependent forces and inverted harmonic potentials to rapidly create large macroscopic quantum superpositions, overcoming previous speed limitations.

Contribution

It introduces a novel integrated method that accelerates the formation of macroscopic superpositions by combining two existing techniques.

Findings

Achieved 50 μm superposition with 10^{-15} kg mass in 0.1 seconds

Demonstrated wave packet evolution in IHP and HP using path integral approach

Proposed a faster method for macroscopic quantum state creation

Abstract

Creating macroscopic spatial superposition states is crucial for investigating matter-wave interferometry and advancing quantum sensor technology. Currently, two potential methods exist to achieve this objective. The first involves using inverted harmonic potential (IHP) to spatially delocalize quantum states through coherent inflation [1]. The second method employs a spin-dependent force to separate two massive wave packets spatially [2]. The disadvantage of the former method is the slow initial coherent inflation, while the latter is hindered by the diamagnetism of spin-embedded nanocrystals, which suppresses spatial separation. In this study, we integrate two methods: first, we use the spin-dependent force to generate initial spatial separation, and second, we use IHP to achieve coherent inflating trajectories of the wavepackets. This approach enables the attainment of massive large spatial superposition in minimal time. For instance, a spatial superposition with a mass of $10^{-15}$ kg and a size of 50 $\mu$m is realized in $0.1$ seconds. We also calculate the evolution of wave packets in both harmonic potential (HP) and IHP using path integral approach.