The emergence domain of an exact ground state in a non-integrable system: the case of the polyphenylene type of chains

Philosophical Magazine Letters

2019

Self Cite

We analyze, in exact terms, multiband 2D itinerant correlated fermionic systems with manybody spin-orbit interactions, and in-plane external magnetic fields. Even if such systems with broad applicability in leading technologies are non-integrable, we set up an exact solution procedure for them, which is described in details. Casting the Hamiltonian in positive semidefinite form, the technique leads to the ground state, and also characterizes the low lying excitation spectrum.PACS numbers:

Section: Introductionmentioning

confidence: 99%

Itinerant surfaces with spin-orbit couplings, correlations and external magnetic fields: exact results

Kucska

Philosophical Magazine Letters

2019

Self Cite

“…As explained in details in Ref. 55 , in a non-integrable case, usually is not possible to obtain the desired solution for the ground state in a single mathematical expression valid for the whole parameter space. Ground state solutions can be written only in a restricted parameter domain which is fixed by the obtained solution of the matching equations.…”

Section: Exact Ground States In the Interacting Case IImentioning

confidence: 99%

Pentagon chain in external fields

Kovács

2015

Philosophical Magazine

Self Cite

We consider a pentagon chain described by a Hubbard type of model considered under periodic boundary conditions. The system i) is placed in an external magnetic field perpendicular to the plane of the cells, and ii) is in a site selective manner under the action of an external electric potential. In these conditions we show in an exact manner that the physical properties of the system can be qualitatively changed. The changes cause first strong modifications of the band structure of the system created by the one-particle part of the Hamiltonian, and second, produce marked changes of the phase diagram. We exemplify this by deducing ferromagnetic ground states in the presence of external fields in two different domains of the parameter space.

“…The difficulty of this job lies in the fact that such systems are non-integrable, and because of this reason, only special techniques are possible to be applied in order to deduce exact results. In this paper we begin to fill up this gap by presenting in our knowledge the first 2D exact ground states for a two band strongly correlated system containing SOI, using the method of positive semidefinite operators whose applicability does not depend on dimensionality and integrability [37][38][39] 38,39,[46][47][48] . Here we focus on magnetic properties and show that given by the interplay of SOI and correlations, ferromagnetism is possible to be induced on surfaces and interfaces increasing in the same time, differentiated for different spin projections, the mobility of carriers.…”

Section: Introductionmentioning

confidence: 99%

Exact results relating spin–orbit interactions in two-dimensional strongly correlated systems

Kucska

2018

Philosophical Magazine

Self Cite

A 2D square, two-bands, strongly correlated and non-integrable system is analysed exactly in the presence of many-body spin-orbit interactions via the method of Positive Semidefinite Operators.The deduced exact ground states in the high concentration limit are strongly entangled, and given by the spin-orbit coupling are ferromagnetic and present an enhanced carrier mobility, which substantially differs for different spin projections. The described state emerges in a restricted parameter space region, which however is clearly accessible experimentally. The exact solutions are provided via the solution of a matching system of equations containing 74 coupled, non-linear and complex algebraic equations. In our knowledge, other exact results for 2D interacting systems with spin-orbit interactions are not present in the literature.