University of Mazandaran
Basic Sciences
The mechanism of the curing reaction between ethylene oxide as a typical epoxy function and tryptophan as an environmentally friendly curing agent was investigated by density functional theory (DFT). A transition state was identified in... more
Infrared (IR) and ultraviolet (UV) spectroscopic analysis of eight structural isomers of C20 carbon nanostructures, i.e. ring, tadpole, bow-tie, dumb-bell, spiro, propellane, bowl and cage, were performed at different levels of theory... more
Most of the linear statistics deal with data lying in a Euclidean space. However, there are many examples, such as DNA molecule topological structures, in which the initial or the transformed data lie in a non-Euclidean space. To get a... more
One of the typical aims of statistical shape analysis, in addition to deriving an estimate of mean shape, is to get an estimate of shape variability. This aim is achieved through employing the principal component analysis. Because the... more
Among many algorithms, gradient descent algorithm (GDA) is a simple tool to derive an optimal quantity in dealing with an optimization problem in the linear space. Apart from the initial value, the step size has a great impact on the... more
We study entanglement Hamiltonian (EH) associated with the reduced density matrix of free fermion models in delocalized-localized Anderson phase transition. We show numerically that the structure of the EH matrix differentiates the... more
We calculate numerically the entanglement entropy of free fermion ground states in one-, two- and three-dimensional Anderson models, and find that it obeys the area law as long as the linear size of the subsystem is sufficiently larger... more
We introduce novel characterizations for many body phase transitions between delocalized and localized phases based on the system's sensitivity to the boundary conditions. In particular, we change single-particle boundary conditions... more
We study the fractal properties of single-particle eigen-modes of entanglement Hamiltonian in free fermion models. One of these modes that has the highest entanglement information and thus called maximally entangled mode (MEM) is... more
We study in this work the ground state entanglement properties of finite XX spin-1/2 chains with random couplings, using Jordan-Wigner transformation. We divide the system into two parts and study reduced density matrices (RDMs) of its... more
We study in this work the ground state entanglement properties of two models of non-interacting fermions moving in one-dimension (1D), that exhibit metal-insulator transitions. We find that entanglement entropy grows either... more
The one-dimensional free Fermi gas is a prototype conformally invariant system, whose entanglement properties are well-understood. In this work, the effects of a single impurity on one dimensional free fermion entanglement entropy are... more
We examine the real space renormalization group method of finding excited eigenstate (RSRG-X) of the XX spin-1/2 chain, from entanglement perspectives. Eigenmodes of entanglement Hamiltonian, especially the maximally entangled mode and... more
Sensitivity of entanglement Hamiltonian spectrum to boundary conditions is considered as a phase detection parameter for delocalized-localized phase transition. By employing one-dimensional models that undergo delocalized-localized phase... more
Single-particle entanglement entropy (SPEE) is calculated for entanglement Hamiltonian eigenmode in a one-dimensional free fermion model that undergoes a delocalized–localized phase transition. In this numerical study, we show that SPEE... more
Entanglement properties of random XX spin 1/2 chain are studied using the random partitioning, in which, sites of the subsystem are chosen randomly with a probability, also the subsystem size varies, and we properly take average over all... more
A characterization of the Anderson phase transition has been introduced, based on the response of the system to the boundary conditions. We change the boundary conditions from periodic to anti-periodic and look for its effect on the... more
Entanglement properties of disordered free fermion systems that have Anderson phase transition between delocalized and localized phases are studied using random bi-partitioning. We use entanglement entropy as a measure to quantify... more
A new characterization of the Anderson phase transition, based on the response of the system to the boundary conditions is introduced. We change the boundary conditions from periodic to antiperiodic and look for its effects on the... more