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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Spin polarization of half-quantum vortex in systems with equal spin pairing
Victor Vakaryuk1, Anthony J Leggett
1Department of Physics, University of Illinois, Urbana, Illinois 61801, USA. vakaryuk@uiuc.edu
Physical Review Letters
|October 2, 2009
Summary
We analyzed half-quantum vortices (HQVs) in equal-spin-pairing superfluids. Our findings show that stable HQVs should exhibit a unique spin polarization, aiding experimental detection.
Area of Science:
- Condensed Matter Physics
- Superfluidity Studies
- Quantum Materials Research
Background:
- Equal-spin-pairing superfluids are theoretically predicted and experimentally sought in materials like Sr2RuO4 and in Helium-3 A-phase.
- Vortices are topological defects in superfluids, and half-quantum vortices (HQVs) represent a distinct type with unique properties.
Purpose of the Study:
- To perform a variational analysis of half-quantum vortices (HQVs) in the equal-spin-pairing superfluid state.
- To identify unique characteristics of HQVs that could aid in their experimental detection.
Main Methods:
- Utilized a variational approach to describe the HQV.
- Employed a Bardeen-Cooper-Schrieffer (BCS)-like wave function incorporating a spin-dependent boost.
Main Results:
- Predicted that stable half-quantum vortices (HQVs) should be accompanied by a nonzero spin polarization.
- This predicted spin polarization is distinct from the one induced by external Zeeman coupling.
Conclusions:
- The predicted spin polarization serves as a potential experimental indicator for the presence of HQVs.
- This research offers a new avenue for the experimental search and verification of HQVs in relevant physical systems.
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