66 citations · 1.3k across the 97 of their papers we have counts for
49 papers · 1 filter
Classical integrable defects as quasi Bäcklund transformations
Anastasia Doikou
We consider the algebraic setting of classical defects in discrete and continuous integrable theories. We derive the "equations of motion" on the defect point via the space-like an…
Scattering in Twisted Yangians
Jean Avan, Anastasia Doikou, Nikos Karaiskos
We study the bulk and boundary scattering of the sl(N) twisted Yangian spin chain via the solution of the Bethe ansatz equations in the thermodynamic limit. Explicit expressions fo…
A classical variant of the vertex algebra & the auxiliary linear problem
Anastasia Doikou
We propose a classical analogue of the vertex algebra in the context of classical integrable field theories. We use this fundamental notion to describe the auxiliary function of th…
Jumps and twists in affine Toda field theories
Anastasia Doikou
The concept of point-like "jump" defects is investigated in the context of affine Toda field theories. The Hamiltonian formulation is employed for the analysis of the problem. The…
Lax pair formulation in the simultaneous presence of boundaries and defects
Anastasia Doikou
Inspired by recent results on the effect of integrable boundary conditions on the bulk behavior of an integrable system, and in particular on the behavior of an existing defect we…
Classical impurities associated to high rank algebras
Anastasia Doikou
Classical integrable impurities associated to high rank (gl_N) algebras are investigated. A particular prototype i.e. the vector non-linear Schrödinger (NLS) model is chosen as an…
Transmission matrices in gl(N) & U_q(gl(N)) quantum spin chains
Anastasia Doikou
The gl(N) and U_q(gl(N)) quantum spin chains in the presence of integrable spin impurities are considered. Within the Bethe ansatz formulation, we derive the associated transmissio…
The sine-Gordon model in the presence of defects
Jean Avan, Anastasia Doikou
The sine-Gordon model in the presence of dynamical integrable defects is investigated. This is an application of the algebraic formulation introduced for integrable defects in earl…
Sigma models in the presence of dynamical point-like defects
Anastasia Doikou, Nikos Karaiskos
Point-like Liouville integrable dynamical defects are introduced in the context of the Landau-Lifshitz and Principal Chiral (Faddeev-Reshetikhin) models. Based primarily on the und…
The sine-Gordon model with integrable defects revisited
Jean Avan, Anastasia Doikou
Application of our algebraic approach to Liouville integrable defects is proposed for the sine-Gordon model. Integrability of the model is ensured by the underlying classical r-mat…
Solutions of the Generic Non-Compact Weyl Equation
Anastasia Doikou, Theodora Ioannidou
In this paper, solutions of the generic non-compact Weyl equation are obtained. In particular, by identifying a suitable similarity transformation and introducing a non-trivial cha…
Liouville integrable defects: the non-linear Schrodinger paradigm
Jean Avan, Anastasia Doikou
A systematic approach to Liouville integrable defects is proposed, based on an underlying Poisson algebraic structure. The non-linear Schrodinger model in the presence of a single…
Defects in the discrete non-linear Schrodinger model
Anastasia Doikou
The discrete non-linear Schrodinger (NLS) model in the presence of an integrable defect is examined. The problem is viewed from a purely algebraic point of view, starting from the…
Generalized Landau-Lifshitz models on the interval
Anastasia Doikou, Nikos Karaiskos
We study the classical generalized gl(n) Landau-Lifshitz (L-L) model with special boundary conditions that preserve integrability. We explicitly derive the first non-trivial local…
Integrable quantum spin chains and their classical continuous counterparts
Jean Avan, Anastasia Doikou, Konstadinos Sfetsos
We present certain classical continuum long wave-length limits of prototype integrable quantum spin chains, and define the corresponding construction of classical continuum Lax ope…
The Non-Compact Weyl Equation
Anastasia Doikou, Theodora Ioannidou
A non-compact version of the Weyl equation is proposed, based on the infinite dimensional spin zero representation of the sl_2 algebra. Solutions of the aforementioned equation are…
BPS Monopoles and Open Spin Chains
Anastasia Doikou, Theodora Ioannidou
We construct SU(n+1) BPS spherically symmetric monopoles with minimal symmetry breaking by solving the full Weyl equation. In this context, we explore and discuss the existence of…
Weyl Equation and (Non)-Commutative SU(n+1) BPS Monopoles
Anastasia Doikou, Theodora Ioannidou
We apply the ADHMN construction to obtain the SU(n+1)(for generic values of n) spherically symmetric BPS monopoles with minimal symmetry breaking. In particular, the problem simpli…
Systematic classical continuum limits of integrable spin chains and emerging novel dualities
Jean Avan, Anastasia Doikou, Konstadinos Sfetsos
We examine certain classical continuum long wave-length limits of prototype integrable quantum spin chains. We define the corresponding construction of classical continuum Lax oper…
Contracted and expanded integrable structures
Anastasia Doikou, Konstadinos Sfetsos
We propose a generic framework to obtain certain types of contracted and centrally extended algebras. This is based on the existence of quadratic algebras (reflection algebras and…
Boundary Lax pairs for the Toda field theories
Jean Avan, Anastasia Doikou
Based on the recent formulation of a general scheme to construct boundary Lax pairs,we develop this systematic construction for the affine Toda field theories (ATFT). W…
affine Toda field theories with integrable boundary conditions revisited
Anastasia Doikou
Generic classically integrable boundary conditions for the affine Toda field theories (ATFT) are investigated. The present analysis rests primarily on the underlying…
Non-diagonal reflection for the non-critical XXZ model
Anastasia Doikou
The most general physical boundary -matrix for the open XXZ spin chain in the non-critical regime () is derived starting from the bare Bethe ansazt equations. The b…
Systematic derivation of boundary Lax pairs
Jean Avan, Anastasia Doikou
We systematically derive the Lax pair formulation for both discrete and continuum integrable classical theories with consistent boundary conditions.