Competition/enhancement of two probe order parameters in the unbalanced holographic superconductor

Abstract

We introduce and study a simple unbalanced holographic superconductor model with two scalar order parameters. The attention is focused on the possibility of coexisting orderings corresponding to the concomitant condensation of two scalar operators. Through a probe analysis we show that an attractive or repulsive direct interaction between the two bulk scalars leads respectively to competition and enhancement of the associated condensates. The system at hand is a toy model for studying generic multiple ordering in a strongly coupled context and some comments are given about its applicability to the ferromagnetic unconventional superconductors.1 dmusso@ulb.ac.be arXiv:1302.7205v2 [hep-th]

Coexistence of two vector order parameters: a holographic model for ferromagnetic superconductivity

“…In the former group, besides the p-wave superconductors, we can also find models describing d-wave order parameters [9]. In the latter class we find either models describing multiband superconductors [10,11] or models which investigate the coexistence of different orderings [15][16][17][18][19]. 1 …”

Polarized solutions and Fermi surfaces in holographic Bose-Fermi systems

“…At the macroscopic level, this system too may arise from a Yukawa interaction of a scalar whose charge is twice that of the elementary fermions. 1 For other examples of competing orders in holography see [9][10][11][12][13][14][15][16]. Figure 1.…”

“…It is convenient to describe the fluid using rescaled energy density, pressure and charge density (defined in appendix A.1 and denoted by a hat), which under the local chemical equilibrium condition are given by: 10) whereμ l (r) is the local chemical potential in the bulk, defined in appendix A, and 11) where q f is the elementary charge of the constituent fermions. With respect to the original construction in [24], we allow for both signs of q f , i.e.…”

“…(A.20) 11 We could in principle allow for a non-zero "intrinsic" chemical potential for particle number not related to the fermion charge q f . However our choice avoids possible singularities [24].…”

Chiral ground states in a frustrated holographic superconductor

“…From a viewpoint of the gauge/gravity correspondence [6][7][8], holographic superconductor models with several order parameters are well-studied [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. In particular, a two-scalar model with the Josephson coupling was studied in ref.…”