Local structure of ordered and disordered states of 3He-A in aerogel

TL;DR

This paper theoretically analyzes the local structure and textures of superfluid 3He-A in aerogel, focusing on how disorder and anisotropy influence the orientation of the order parameter.

Contribution

It provides a detailed theoretical analysis of the textures and correlation functions of 3He-A in aerogel, including effects of anisotropy and modifications of the Larkin-Imry-Ma state.

Findings

Correlation functions of orientation angles are derived for small distances.

Modifications of the Larkin-Imry-Ma state under uniaxial stress are characterized.

Characteristic parameters of the disordered states are identified.

Abstract

Random textures of the orbital part of the order parameter of superfluid 3He-A in aerogel are analyzed theoretically in the Ginzburg and Landau region both in the presence and in the absence of a global anisotropy. Correlation functions of angles, determining orientation of the order parameter are found for relative distances which are small in comparison with the characteristic scale of the random texture. Modifications of the Larkin-Imry-Ma state in limiting cases of a relatively strong uniaxial compression and of a uniaxial stretching are analyzed and characteristic parameters of the emerging states are found.