| Autor: |
Gannon, W. J., Zaliznyak, I. A., Wu, L. S., Feiguin, A. E., Tsvelik, A. M., Demmel, F., Qiu, Y., Copley, J. R. D., Kim, M. S., Aronson, M. C. |
| Rok vydání: |
2019 |
| Předmět: |
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| Zdroj: |
Nature Communications 10, 1123 (2019) |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1038/s41467-019-08715-y |
| Popis: |
The fundamental excitations in an antiferromagnetic chain of spins-1/2 are spinons, de-confined fractional quasiparticles that when combined in pairs, form a triplet excitation continuum. In an Ising-like spin chain the continuum is gapped and the ground state is N{\'e}el ordered. Here, we report high resolution neutron scattering experiments, which reveal how a magnetic field closes this gap and drives the spin chains in \YPP\ to a critical, disordered Luttinger-liquid state. In \YPP\ the effective spins-1/2 describe the dynamics of large, Ising-like Yb magnetic moments, ensuring that the measured excitations are exclusively longitudinal, which we find to be well described by time-dependent density matrix renormalization group calculations. The inter-chain coupling leads to the confinement of spinons, a condensed matter analog of quark confinement in quantum chromodynamics. Insensitive to transverse fluctuations, our measurements show how a gapless, dispersive longitudinal mode arises from confinement and evolves with magnetic order. |
| Databáze: |
arXiv |
| Externí odkaz: |
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