In this pedagogical review we introduce systematic approaches to deforming integrable two-
dimensional sigma models. We use the integrable principal chiral model and the conformal …

These are pedagogical lecture notes discussing current–current deformations of 2-
dimensional field theories. The deformations that are considered here are generated …

We show that the so-called λ deformed σ-model as well as the η deformed one belong to a
class of the E-models introduced in the context of the Poisson–Lie-T-duality. The λ and η …

A bstract The worldsheet theories that describe Poisson-Lie T-dualisable σ-models on group
manifolds as well as integrable η, λ and β-deformations provide examples of ℰ-models …

A bstract We derive the part of the Lagrangian for the sigma model on the η-deformed AdS
5× S 5 space which is quadratic in fermions and has the full dependence on bosons. We …

We prove that abelian Yang–Baxter deformations of superstring coset σ models are
equivalent to sequences of commuting TsT transformations, meaning T dualities and …

A bstract We study the renormalisation of a large class of integrable σ-models obtained in
the framework of affine Gaudin models. They are characterised by a simple Lie …

In the approach recently proposed by K. Costello and M. Yamazaki, which is based on a four-
dimensional variant of Chern–Simons theory, we derive a simple and unifying two …

A bstract We introduce a new elliptic integrable σ-model in the form of a two-parameter
deformation of the Principal Chiral Model on the group SL ℝ (N), generalising a construction …

We construct the actions of a very broad family of 2d integrable $\sigma $-models. Our
starting point is a universal 2d action obtained in [arXiv: 2008.01829] using the framework of …