We present the phase diagram and critical properties of a coupled XY Ising model on a triangular lattice using the mean-field approximation, the Migdal-Kadanoff scheme of renormalization group and Monte-Carlo simulations. The topology of the phase diagram is similar for the three techniques, with the appearance of a phase with XY order and Ising disorder. The results suggest a line of transitio...

We study the phase diagram of the three-dimensional classical ferromagnetic Heisenberg model with an easyplane crystalline anisotropy and an easy-axis exchange anisotropy through Monte Carlo simulations. We employ the Metropolis algorithm together with single-histogram techniques in order to characterize the transitions in each region of the phase diagram. Our results reveal, besides the disord...

For an integral parameter t ∈ Z we investigate the family of Thue equations F (x, y) = x + (t− 1)xy − (2t + 4t + 4)xy + (t + t + 2t + 4t − 3)xy + (t + t + 5t+ 3)xy + y = ±1 , originating from Emma Lehmer’s family of quintic fields, and show that for |t| ≥ 3.28 ·1015 the only solutions are the trivial ones with x = 0 or y = 0. Our arguments contain some new ideas in comparison with the standard ...

We investigate the ground state and critical temperature phase diagrams of classical quantum $S=1/2$ pyrochlore lattice with nearest-neighbor Heisenberg Dzyaloshinskii-Moriya interactions (DMI). consider ferromagnetic antiferromagnetic exchange as well direct indirect DMI. Classically, three states are found: all-in/all-out, a locally ordered $XY$ phase, known $\Gamma_5$, which displays an acci...

In this work, we investigate the quantum phase transition in a non-Hermitian XY spin chain. The diagram shows that critical points of Ising expand into zone after introducing effect. By analyzing gap and long-range correlation function, one can distinguish different phases by means features decay properties tricky problem traditional model. Furthermore, results reveal relationship among regions...

We present a process semantics for the purely additive fragment of linear logic in which formulas denote protocols and (equivalence classes of) proofs denote multichannel concurrent processes. The polycategorical model induced by this process semantics is shown to be equivalent to the free polycategory based on the syntax (i.e., it is full and faithfully complete). This establishes that the add...

XX cells from XX/XY hemopoietic chimeras do not express male determinants in a way to render them either stimulators or targets for male-specific cytotoxic lymphocytes. XX- but not XY-responder T cells from chimeras can be activated to lyse allogeneic male target cells; T cells from normal XX mice depleted of alloreactive T cells, however, cannot be sensitized to lyse allogeneic XY targets. The...

We conclude thhat T is a subgroup. Now we exhibit an example where T fails to be a subgroup when G is non-abelian. Let G = 〈x, y|x = y = i 〉. Observe that the product xy has infinite order since the product (xy)(xy) is no longer reducible because we lack the commutativity of x with y. Hence, x, y ∈ T but (xy) / ∈ T . Exercise (7). Fix some n ∈ Z with n > 1. Find the torsion subgroup of Z×(Z/nZ)...