Abstract
The low-energy magnetic excitation spectrum of the Heisenberg antiferromagnetic S=1/2 chain system Sr2CuO3 with Ni and Ca impurities is studied by neutron spectroscopy. In all cases, a defect-induced spectral pseudogap is observed and shown to scale proportionately to the number of scattering centers in the spin chains.
| Original language | English |
|---|---|
| Article number | 054409 |
| Journal | Physical Review B |
| Volume | 95 |
| Issue number | 5 |
| DOIs | |
| State | Published - Feb 7 2017 |
Funding
This work was supported by the Swiss National Science Foundation, Division 2. The work at IFW was supported by the Deutsche Forschungsgemeinschaft through D-A-CH Project No. HE 3439/12 and the European Commission through the LOTHERM project (Project No. PITN-GA-2009-238475). The neutron scattering experiments at Oak Ridge National Laboratory's Spallation Neutron Source were sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. The experiment at the MLZ was financially supported by EU Framework 7 program NMI3. Additional support for the work at ILL was provided by the Swiss State Secretariat for Education, Research and Innovation (SERI) through a CRG grant.