Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1812.09948

Matter-wave interferometry using a levitated magnetic nanoparticle

Anisur Rahman

Published Dec 24, 2018• 0 citations
arXivHTMLPDF

Abstract

The superposition principle is one of the bizarre predictions of quantum mechanics. Nevertheless, it has been experimentally verified using electrons, photons, atoms, and molecules. In this article, using a $20~$nm levitated ferromagnetic FePt nanoparticle, an exotic all optical spin polarization technique and the matter-wave interferometry, we show that a mesoscopic spatial Schrodinger cat can be created. Additionally, we argue that the maximum spatial separation between the delocalized wavepackets can be $25~μm$ and is significantly larger than the object itself.

DOI
10.48550/arxiv.1812.09948

Related papers

Large spatial Schrödinger cat state using a levitated ferrimagnetic nanoparticle

Anisur Rahman

Abstract The superposition principle is one of the main tenets of quantum mechanics. Despite its counter-intuitiveness, it has been experimentally verified using electrons, photons, atoms, and molecules. However, a similar experimental demonstration using a nano or a micro particle is non-existent. Here in this article, exploiting macroscopic quantum coherence and quantum tunneling, we propose an experiment using a levitated magnetic nanoparticle to demonstrate such an effect. It is shown that the spatial separation between the delocalized wavepackets of a 20 nm ferrimagnetic yttrium iron garnet (YIG) nanoparticle can be as large as 5 μm. We argue that, in addition to using for testing one of the most fundamental aspects of quantum mechanics, this scheme can simultaneously be used to test different modifications, such as wavefunction collapse models, to the standard quantum mechanics. Furthermore, we show that the spatial superposition of a core–shell structure, a YIG core and a non-magnetic silica shell, can be used to probe quantum gravity.

arXiv:1907.00415•New Journal of Physics•Oct 21, 2019•24 citations

Spatial superposition at a millimetre scale length using a levitated ferromagnetic nanoparticle

Anisur Rahman

The superposition principle is one of the bizarre predictions of quantum mechanics. Nevertheless, it has been experimentally verified using electrons, photons, atoms, and molecules. However, a similar experimental demonstration using a nano or micro particle is still missing and various proposals have been put forward in the literature for creating such a state. In the existing proposals, the attainable spatial separations between the delocalized states are less than the size of the particles that have been used to create such states. In this article, using a $50~$nm levitated ferromagnetic particle and existing technologies, we show that a spatial separation of $1~$mm between the superposed states is readily achievable. This may lead to the possibility of testing quantum gravity, collapse models and gravity induced state reduction.

•Dec 24, 2018•0 citations

Probing quantum mechanics with nanoparticle matter-wave interferometry

Sebastian Pedalino, Bruno E. Ramírez-Galindo, Richard Ferstl +3 more

Abstract The quantum superposition principle is a fundamental concept of physics 1 and the basis of numerous quantum technologies 2,3 . Yet, it is still often regarded counterintuitive because we do not observe its key features on the macroscopic scales of our daily lives. It is, therefore, interesting to ask how quantum properties persist or change as we increase the size and complexity of objects 4 . A model test for this question can be realized by matter-wave interferometry, in which the motion of individual massive particles becomes delocalized and needs to be described by a wave function that spans regions far larger than the particle itself 5 . Over the years, this has been explored with a series of objects of increasing mass and complexity 6–9 and a growing community aims at pushing this to ever larger limits. Here we present an experimental platform that extends matter-wave interference to large metal clusters, a qualitatively new material class for quantum experiments. We specifically demonstrate quantum interference of sodium nanoparticles, which can each contain more than 7,000 atoms at masses greater than 170,000 Da. They propagate in a Schrödinger cat state with a macroscopicity 10 of μ = 15.5, surpassing previous experiments 5,9,11 by an order of magnitude.

Nature•Jan 21, 2026•25 citations

Mesoscopic mechanical superpositions by gluing individual quantum systems

Thiago Guerreiro

We propose a protocol for preparing mechanical Schrödinger kittens -- mesoscopic quantum superpositions of coherent motional states of an optically levitated nanoparticle -- by adhering single electron time-bin states to its surface. Over short protocol timescales, coherence of the mesoscopic superposition survives the dominant decoherence mechanisms afflicting levitated systems, and can be observed by varying the phase of the time-bin electrons. Interference fringes can be detected with real-time, near-Heisenberg limited interferometry of photons scattered from the particle. This approach eliminates the need for coherent state expansion, dark potentials, and particle release-and-recapture mechanisms, providing a new route to test quantum mechanics in unprecedented scales.

quant-pharXiv:2607.20195•Jul 23, 2026•0 citations

Quantum Delocalization of a Levitated Nanoparticle

Massimiliano Rossi, Andrei Militaru, N. Carlon Zambon +4 more

Matter waves have been observed in double-slit experiments with microscopic objects, such as atoms or molecules. The wave function describing the motion of these objects must extend over a distance comparable to the slit separation, much larger than the characteristic size of the objects. Preparing such states for more massive objects, such as mechanical oscillators, remains an outstanding challenge. Here we delocalize the quantum ground state of an optically levitated nanosphere by modulating the stiffness of the confining potential. We show a more than threefold increase of the initial coherence length, which corresponds to mechanical momentum squeezing of more than 7 dB. Our work is a stepping stone toward the generation of coherence lengths comparable to the object size, a crucial regime for macroscopic quantum experiments.

Physical Review Letters•Jun 24, 2025•29 citations

Quantum Interference of Clusters and Large Molecules

Nadine Dörre

I will discuss recent advances in matter-wave experiments which exploit the quantum delocalization of nanoparticles. De Broglie wave interferometers allow tests of the quantum superposition principle for mesoscopic objects and new avenues to molecule metrology.

Frontiers in Optics•Jan 1, 2013•0 citations
The superposition principle is one of the bizarre predictions of quantum mechanics. Nevertheless, it has been experimentally verified using electrons, photons, atoms, and molecules. In this article, using a 20 20~20 nm levitated ferromagnetic FePt nanoparticle, an exotic all optical spin polarization technique and the matter-wave interferometry, we show that a mesoscopic spatial Schrodinger cat can be created. Additionally, we argue that the maximum spatial separation between the delocalized wavepackets can be 25 μm25~μm25 μm and is significantly larger than the object itself.
Abstract The superposition principle is one of the main tenets of quantum mechanics. Despite its counter-intuitiveness, it has been experimentally verified using electrons, photons, atoms, and molecules. However, a similar experimental demonstration using a nano or a micro particle is non-existent. Here in this article, exploiting macroscopic quantum coherence and quantum tunneling, we propose an experiment using a levitated magnetic nanoparticle to demonstrate such an effect. It is shown that the spatial separation between the delocalized wavepackets of a 20 nm ferrimagnetic yttrium iron garnet (YIG) nanoparticle can be as large as 5 μm. We argue that, in addition to using for testing one of the most fundamental aspects of quantum mechanics, this scheme can simultaneously be used to test different modifications, such as wavefunction collapse models, to the standard quantum mechanics. Furthermore, we show that the spatial superposition of a core–shell structure, a YIG core and a non-magnetic silica shell, can be used to probe quantum gravity.
The superposition principle is one of the bizarre predictions of quantum mechanics. Nevertheless, it has been experimentally verified using electrons, photons, atoms, and molecules. However, a similar experimental demonstration using a nano or micro particle is still missing and various proposals have been put forward in the literature for creating such a state. In the existing proposals, the attainable spatial separations between the delocalized states are less than the size of the particles that have been used to create such states. In this article, using a 50 50~50 nm levitated ferromagnetic particle and existing technologies, we show that a spatial separation of 1 1~1 mm between the superposed states is readily achievable. This may lead to the possibility of testing quantum gravity, collapse models and gravity induced state reduction.
Abstract The quantum superposition principle is a fundamental concept of physics 1 and the basis of numerous quantum technologies 2,3 . Yet, it is still often regarded counterintuitive because we do not observe its key features on the macroscopic scales of our daily lives. It is, therefore, interesting to ask how quantum properties persist or change as we increase the size and complexity of objects 4 . A model test for this question can be realized by matter-wave interferometry, in which the motion of individual massive particles becomes delocalized and needs to be described by a wave function that spans regions far larger than the particle itself 5 . Over the years, this has been explored with a series of objects of increasing mass and complexity 6–9 and a growing community aims at pushing this to ever larger limits. Here we present an experimental platform that extends matter-wave interference to large metal clusters, a qualitatively new material class for quantum experiments. We specifically demonstrate quantum interference of sodium nanoparticles, which can each contain more than 7,000 atoms at masses greater than 170,000 Da. They propagate in a Schrödinger cat state with a macroscopicity 10 of μ = 15.5, surpassing previous experiments 5,9,11 by an order of magnitude.
We propose a protocol for preparing mechanical Schrödinger kittens -- mesoscopic quantum superpositions of coherent motional states of an optically levitated nanoparticle -- by adhering single electron time-bin states to its surface. Over short protocol timescales, coherence of the mesoscopic superposition survives the dominant decoherence mechanisms afflicting levitated systems, and can be observed by varying the phase of the time-bin electrons. Interference fringes can be detected with real-time, near-Heisenberg limited interferometry of photons scattered from the particle. This approach eliminates the need for coherent state expansion, dark potentials, and particle release-and-recapture mechanisms, providing a new route to test quantum mechanics in unprecedented scales.
Matter waves have been observed in double-slit experiments with microscopic objects, such as atoms or molecules. The wave function describing the motion of these objects must extend over a distance comparable to the slit separation, much larger than the characteristic size of the objects. Preparing such states for more massive objects, such as mechanical oscillators, remains an outstanding challenge. Here we delocalize the quantum ground state of an optically levitated nanosphere by modulating the stiffness of the confining potential. We show a more than threefold increase of the initial coherence length, which corresponds to mechanical momentum squeezing of more than 7 dB. Our work is a stepping stone toward the generation of coherence lengths comparable to the object size, a crucial regime for macroscopic quantum experiments.