Publications by authors named "Mohammad R Kolahchi"

We demonstrate the manifestations of nonlinear features in magnetic dynamics and - characteristics of a φ Josephson junction in the ferromagnetic resonance region. We show that at small values of the system parameters damping, spin-orbit interaction, and Josephson-to-magnetic energy ratio, the magnetic dynamics is reduced to the dynamics of a scalar Duffing oscillator driven by the Josephson oscillations. The role of the increasing superconducting current in the resonance region is clarified.

View Article and Find Full Text PDF

Chimera states are spatiotemporal segregations - stably coexisting coherent and incoherent groups - that can occur in systems of identical phase oscillators. Here we demonstrate that this remarkable phenomenon can also be understood in terms of Pecora and Carroll's drive-response theory. By calculating the conditional Lyapunov exponents, we show that the incoherent group acts to synchronize the coherent group; the latter playing the role of a response.

View Article and Find Full Text PDF

The interplay between electrostatic interactions and orientational correlations is studied for a model system of charged rods positioned on a chain, using Monte Carlo simulation techniques. It is shown that the coupling brings about the notion of electrostatic frustration, which in turn results in: (i) a rich variety of orientational orderings such as chiral phases, and (ii) an inherently slow dynamics characterized by stretched-exponential behavior in the relaxation functions of the system.

View Article and Find Full Text PDF