Abstract
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 Néel ordered. Here, we report high resolution neutron scattering experiments, which reveal how a magnetic field closes this gap and drives the spin chains in Yb 2 Pt 2 Pb to a critical, disordered Luttinger-liquid state. In Yb 2 Pt 2 Pb 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.
| Original language | English |
|---|---|
| Article number | 1123 |
| Journal | Nature Communications |
| Volume | 10 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 1 2019 |
Bibliographical note
Publisher Copyright:© 2019, The Author(s).
Funding
Work at Texas A&M University (W.J.G. and M.C.A) was supported by NSF-DMR-1310008. Work at Brookhaven National Laboratory (I.A.Z. and A.M.T.) was supported under the auspices of the US Department of Energy, Office of Basic Energy Sciences, under contract DE-SC00112704. Work at Northeastern University (A.E.F.) was supported by the US Department of Energy, Office of Science, Basic Energy Sciences grant number DE-SC0014407. Work at the ISIS neutron source was partly supported by the Science and Technology Facilities Council, STFC. Access to DCS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Institute of Standards and Technology and the National Science Foundation under Agreement No. DMR-1508249. We thank S.E. Nagler and R. Vega-Morales for helpful discussions about this work.
| Funders | Funder number |
|---|---|
| Science and Technology Facilities Council | |
| U.S. Department of Energy Oak Ridge National Laboratory U.S. Department of Energy National Science Foundation National Energy Research Scientific Computing Center | |
| National Institute of Standards and Technology | |
| National Science Foundation Office of International Science and Engineering | |
| Northeastern University, China | |
| Brookhaven National Laboratory (BNL) | |
| U.S. Department of Energy Chinese Academy of Sciences Guangzhou Municipal Science and Technology Project Oak Ridge National Laboratory Extreme Science and Engineering Discovery Environment National Science Foundation National Energy Research Scientific Computing Center National Natural Science Foundation of China | DMR-1508249, 1807451 |
| U.S. Department of Energy Chinese Academy of Sciences Guangzhou Municipal Science and Technology Project Oak Ridge National Laboratory Extreme Science and Engineering Discovery Environment National Science Foundation National Energy Research Scientific Computing Center National Natural Science Foundation of China | |
| UK Industrial Decarbonization Research and Innovation Centre | 103601 |
| UK Industrial Decarbonization Research and Innovation Centre | |
| DOE Basic Energy Sciences | DE-SC00112704, DE-SC0014407 |
| DOE Basic Energy Sciences | |
| Texas AandM University | NSF-DMR-1310008 |
| Texas AandM University |
ASJC Scopus subject areas
- General Chemistry
- General Biochemistry, Genetics and Molecular Biology
- General Physics and Astronomy