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Resolving Nonclassical Magnon Composition of a Magnetic Ground State via a Qubit
Anna-Luisa E Römling1, Alejandro Vivas-Viaña1, Carlos Sánchez Muñoz1
1Condensed Matter Physics Center (IFIMAC) and Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
Physical Review Letters
|October 20, 2023
Summary
Researchers show how to detect and control quantum squeezing in magnons using a qubit. This method allows for the deterministic generation of squeezed states, opening new avenues in quantum technologies.
Area of Science:
- Quantum physics
- Condensed matter physics
- Quantum information science
Background:
- Magnons, the quanta of magnetic excitations, exhibit quantum properties like squeezing and entanglement.
- Exploiting these quantum properties in magnets requires concrete experimental protocols.
- Current understanding of magnetic quantum states needs practical applications for quantum science and technology.
Purpose of the Study:
- To theoretically demonstrate a method for detecting quantum superposition in magnonic ground states.
- To show how a qubit-magnon coupling can control equilibrium magnon squeezing.
- To enable the deterministic generation of squeezed even Fock states using qubit manipulation.
Main Methods:
- Theoretical modeling of a direct dispersive coupling between a qubit and a noneigenmode magnon.
- Utilizing qubit excitation spectroscopy to probe magnonic quantum states.
- Analyzing the control pathways offered by the qubit state and its excitation.
Main Results:
- Detection of magnonic number states' quantum superposition via qubit excitation spectroscopy.
- Demonstration of control over equilibrium magnon squeezing through qubit-magnon coupling.
- Deterministic generation of squeezed even Fock states is achieved via qubit control.
Conclusions:
- Direct dispersive coupling to noneigenmodes is a viable pathway for exploiting magnon quantum properties.
- This approach is realizable in existing spin systems.
- Motivates further research into similar quantum control mechanisms in other physical platforms.
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