Magnon-magnon entanglement and its quantification via a microwave cavity

Mousolou, Vahid Azimi; Liu, Yuefei; Bergman, Anders; Delin, Anna; Eriksson, Olle; Pereiro, Manuel; Thonig, Danny; Sjöqvist, Erik

doi:10.1103/physrevb.104.224302

Cited by 32 publications

(14 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Various metrics, such as von Neumann entropy [161,162] and concurrence [160,229,230], have been employed in quantifying this entanglement content [138,231], as introduced above in Section 2.2. Special focus has been on antiferromagnets [161,229,230,232,233] which manifest very large squeeze parameters, and entanglement, due to exchange interaction causing the squeezing [21,161]. In contrast, relatively weak anisotropy leads to squeezing in ferromagnets.…”

Section: Squeezed Statesmentioning

confidence: 99%

“…They showed that magnons with opposite wave vectors are always created in pairs and their entanglement, as quantified by the DGCZ inequality [166], decreases at the corners of Brillouin zone. Mousolou et al [232] identified the relation between bipartite magnon entanglement and the EPR function and proposed a measurement setup based on the interaction of light and antiferromagnets, as shown in Fig. 14(b).…”

Section: Magnon-magnon Entanglementmentioning

confidence: 99%

See 1 more Smart Citation

Quantum magnonics: when magnon spintronics meets quantum information science

Yuan

2022

Preprint

View full text Add to dashboard Cite

Spintronics and quantum information science are two promising candidates for innovating information processing technologies. The combination of these two fields enables us to build solid-state platforms for studying quantum phenomena and for realizing multi-functional quantum tasks. For a long time, however, the intersection of these two fields was limited due to the distinct properties of the classical magnetization, that is manipulated in spintronics, and quantum bits, that are utilized in quantum information science. This situation has changed significantly over the last few years because of the remarkable progress in coding and processing information using magnons. On the other hand, significant advances in understanding the entanglement of quasi-particles and in designing high-quality qubits and photonic cavities for quantum information processing provide physical platforms to integrate magnons with quantum systems. From these endeavours, the highly interdisciplinary field of quantum magnonics emerges, which combines spintronics, quantum optics and quantum information science. Here, we give an overview of the recent developments concerning the quantum states of magnons and their hybridization with mature quantum platforms. First, we review the basic concepts of magnons and quantum entanglement and discuss the generation and manipulation of quantum states of magnons, such as single-magnon states, squeezed states and quantum many-body states including Bose-Einstein condensation and the resulting spin superfluidity. We discuss how magnonic systems can be integrated and entangled with quantum platforms including cavity photons, superconducting qubits, nitrogen-vacancy centers, and phonons for coherent information transfer and collaborative information processing. The implications of these hybrid quantum systems for non-Hermitian physics and parity-time symmetry are highlighted, together with applications in quantum memories and high-precision measurements. Finally, we present an outlook on some of the challenges and opportunities in quantum magnonics.

show abstract

Section: Squeezed Statesmentioning

confidence: 99%

Section: Magnon-magnon Entanglementmentioning

confidence: 99%

Quantum magnonics: when magnon spintronics meets quantum information science

Yuan

2022

Preprint

View full text Add to dashboard Cite

show abstract

“…As a result, strong and ultrastrong coupling of ferromagnetic magnons to microwave photons in a superconducting cavity has been experimentally demonstrated [32][33][34][35]. In such hybrids, many intriguing phenomena have been studied, including magnon nonclassical states [36][37][38][39][40][41][42][43], Floquet engineering [44], spin currents [45,46], magnon-induced nonreciprocity [47][48][49][50][51][52], non-Hermitian physics [53][54][55][56][57][58], and dark matter detection [59][60][61].…”

Section: Introductionmentioning

confidence: 99%

Chiral coupling between a ferromagnetic magnon and a superconducting qubit

Ren¹,

Ma²,

Li³

2022

Preprint

View full text Add to dashboard Cite

Chiral coupling at the single-quantum level promises to be a remarkable potential for quantum information processing. Here we propose to achieve a chiral interaction between a magnon mode in a ferromagnetic sphere and a superconducting qubit mediated by a one-dimensional coupled-cavity array. When the qubit is coupled to two lattice sites of the array and each one is encoded with a tunable phase, we can acquire a directional qubit-magnon interaction via the quantum interference effect. This work opens up a new route to construct chiral devices, which are expected to become a building block in quantum magnonic networks.

show abstract

“…Strong magnonic coupling to superconducting qubits [3,5], photons [6][7][8][9], and phonons [10][11][12][13] has been demonstrated. This has triggered a wide range of theoretical proposals suggesting the use of magnonic nonclassical states in providing a resource of entanglement and memories for quantum communication and information processing [4,[14][15][16][17][18][19][20][21][22][23].…”

mentioning

confidence: 99%

Pure dephasing of magnonic quantum states

Yuan,

Sterk,

Kamra

et al. 2022

Preprint

View full text Add to dashboard Cite

For a wide range of nonclassical magnonic states that have been proposed and demonstrated recently, a new time scale besides the magnon lifetime -the magnon dephasing time -becomes important, but this time scale is rarely studied. Considering exchange interaction and spin-phonon coupling, we evaluate the pure magnon dephasing time and find it to be smaller than the magnon lifetime at temperatures of a few Kelvins. By examining a magnonic cat state as an example, we show how pure dephasing of magnons destroys and limits the survival of quantum superpositions. Thus it will be critical to perform quantum operations within the pure dephasing time. We further derive the master equation for the density matrix describing such magnonic quantum states taking into account the role of pure dephasing, whose methodology can be generalized to include additional dephasing channels that experiments are likely to encounter in the future. Our findings enable one to design and manipulate robust quantum states of magnons for information processing.

show abstract

Magnon-magnon entanglement and its quantification via a microwave cavity

Cited by 32 publications

References 32 publications

Quantum magnonics: when magnon spintronics meets quantum information science

Quantum magnonics: when magnon spintronics meets quantum information science

Chiral coupling between a ferromagnetic magnon and a superconducting qubit

Pure dephasing of magnonic quantum states

Contact Info

Product

Resources

About