Related papers: Linear theory of random textures of 3He-A in aerog…
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…
A mutual action of the random anisotropy brought in the superfluid 3He by aerogel and of the global anisotropy caused by its deformation is considered. Strong global anisotropy tends to suppress fluctuations of orientation of the order…
Deformed aerogels induce a global anisotropy in the superfluid 3He and orient the orbital part of its order parameter. Here a phenomenological theory of the orientational effect of elastic deformations of aerogels on the superfluid phases…
Highly anisotropic "nematically ordered" aerogel induces global uniaxial anisotropy in superfluid 3He. The anisotropy lowers symmetry of 3He in aerogel from spherical to axial. As a result instead of one transition temperature in the state,…
We report on orientation of the order parameter in the 3He-A and 3He-B phases caused by aerogel anisotropy. In 3He-A we have observed relatively homogeneous NMR line with an anomalously large negative frequency shift. We can attribute this…
Superfluid 3He-A shares the properties of spin nematic and chiral orbital ferromagnet. Its order parameter is characterized by two vectors d and l. This doubly anisotropic superfluid, when it is confined in aerogel, represents the most…
The orbital anisotropy induced in the superfluid 3He by nematic aerogel is, generally speaking, spatially non-uniform. This anisotropy in its turn induces spatial fluctuations of the order parameter. It is shown here that for the polar…
Within a phenomenological approach possible forms of the order parameter of the superfluid phases of 3He in a vicinity of the transition temperature are discussed. Effect of aerogel is described by a random tensor field interacting with the…
The anisotropic superfluid 3He-A in aerogel provides an interesting example of a system with continuous symmetry in the presence of random anisotropy disorder. Recent NMR experiments allow us to discuss two regimes of the orientational…
We perform cluster aggregation simulations to model the structure of anisotropic aerogel. By biasing the diffusion process, we are able to obtain two distinct types of globally anisotropic aerogel structures which we call "nematic", with…
Deformation of aerogel strongly modifies the orientation of the order parameter of superfluid 3He confined in aerogel. We used a radial squeezing of aerogel to keep the orbital angular momentum of the 3He Cooper pairs in the plane…
Superfluid 3He-A in a fully characterized stretched aerogel, used in previous work [1], has been studied for parallel and perpendicular orientations of the magnetic field relative to the anisotropy axis of the aerogel. Consistently, we find…
It was found that NMR properties of both superfluid phases of $^3$He in anisotropic aerogel can be described in terms of the bulk superfluid order parameters with the orbital order parameter vector fixed by anisotropy of the aerogel sample.…
Glass states of superfluid A-like phase of 3He in aerogel induced by random orientations of aerogel strands are investigated theoretically and experimentally. In anisotropic aerogel with stretching deformation two glass phases are observed.…
NMR experiments on liquid $^3$He infused into uniaxially anisotropic silica aerogels show the stabilisation of two equal-spin-pairing chiral phases on cooling from the normal phase. The alignment of the chiral axis relative to the…
It is established theoretically that an ordered state with continuous symmetry is inherently unstable to arbitrarily small amounts of disorder [1, 2]. This principle is of central importance in a wide variety of condensed systems including…
The A and B phases of superfluid 3 He have vector degrees of freedom that reflect their characteristic broken symmetries, respectively chiral and spin-orbit rotation axes. Anisotropic disorder in the superfluid, imbibed in uniformly…
One of the most spectacular discoveries made in superfluid $^3$He confined in a nanostructured material like aerogel or nafen was the observation of the destruction of the long-range orientational order by a weak random anisotropy. The…
Anisotropic aerogel possesses structure which exhibits a strong influence over the composition and orientation of the order parameter of imbibed superfluid $^3$He. Computational studies have identified stretched aerogel with plane-like…
Effect of uniaxially-deformed aerogel on orientation of the order parameter of superfluid $^3He$ is considered. Approach used takes into account correlations in positions of particles forming aerogel. Calculations show that for the case of…