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Published on: July 8, 2021
Fermi surface topology and the superconducting gap function in UPd2Al3: a neutron spin-echo study
E Blackburn1, A Hiess, N Bernhoeft
1Institut Laue-Langevin, Boîte Postale 156, F-38042 Grenoble, France.
Physical Review Letters
|October 10, 2006
Summary
Antiferromagnetic quasielastic scattering is absent in the heavy-fermion superconductor UPd2Al3 within the superconducting phase. This finding, observed using neutron spin-echo, limits models of this magnetic superconductor.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Heavy-fermion superconductors exhibit complex interplay between magnetism and superconductivity.
- UPd2Al3 is a prominent heavy-fermion superconductor displaying antiferromagnetic order in its normal state.
Purpose of the Study:
- To investigate the low-energy dynamic response of UPd2Al3.
- To determine the behavior of antiferromagnetic fluctuations within the superconducting phase.
Main Methods:
- Single crystal neutron spin-echo spectroscopy.
- Probing dynamics near the antiferromagnetic wave vector Q(0)=(0 0 0.5).
Main Results:
- Absence of antiferromagnetic quasielastic scattering well inside the superconducting phase.
- Observed absence for relaxation times up to 10 nanoseconds.
- Achieved energy resolution of approximately 1 microeV.
Conclusions:
- The absence of magnetic scattering strongly constrains theoretical models.
- Suggests a significant modification or suppression of magnetic fluctuations by superconductivity.
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