d-Wave Spin Density Wave phase in the Attractive Hubbard Model with Spin Polarization

TL;DR

This paper explores the emergence of a transverse d-wave spin density wave in the attractive Hubbard model with spin polarization, linking it to d-wave superfluidity and predicting its realization in cold atom gases and certain materials.

Contribution

It introduces a novel d-wave SDW phase induced by pairing and density fluctuations in a spin-polarized attractive Hubbard model, connecting it to superfluidity via a transformation.

Findings

Identification of transverse d-wave SDW near half-filling.

Connection between SDW and d-wave superfluidity through Shiba's transformation.

Predictions for observing the SDW in cold atom gases and materials.

Abstract

We investigate the possibility of unconventional spin density wave (SDW) in the attractive Hubbard model with finite spin polarization. We show that pairing and density fluctuations induce the transverse d-wave SDW near the half-filling. This novel SDW is related to the d-wave superfluidity induced by antiferromagnetic spin fluctuations, in the sense that they are connected with each other through Shiba's attraction-repulsion transformation. Our results predict the d-wave SDW in real systems, such as cold Fermi atom gases with population imbalance and compounds involving valence skipper elements.