相关论文: Magnetocaloric effect in integrable spin-s chains
We study the magnetocaloric effect for the integrable antiferromagnetic Heisenberg spin chain with competing interactions. We computed the Gr\"uneisen parameter, which is closely related to the magnetocaloric effect, for the quantum spin…
We compute the entropy of antiferromagnetic quantum spin-s chains in an external magnetic field using exact diagonalization and Quantum Monte Carlo simulations. The magnetocaloric effect, i.e., temperature variations during adiabatic field…
The magnetocaloric effect in the symmetric spin-1/2 Ising-Heisenberg diamond chain with the Ising four-spin interaction is investigated using the generalized decoration-iteration mapping transformation and the transfer-matrix technique. The…
Magnetocaloric effect in a double-tetrahedral chain, in which nodal lattice sites occupied by the localized Ising spins regularly alternate with three equivalent lattice sites available for mobile electrons, is exactly investigated by…
We study the magnetocaloric effect (MCE) in spin clusters of six spins with site spins $s=1$, $3/2$ and $2$ for different exchange anisotropies. We also study MCE in an assembly of spin clusters, on a chain, a 2-D square lattice and 3-D…
The magnetic analog of the Gr\"{u}neisen parameter, i.e., the magnetocaloric effect, is a valuable tool for studying field-tuned quantum phase transitions. We determine the magnetic Gr\"{u}neisen parameter of the one-dimensional random…
We calculate the entropy and cooling rate of the antiferromagnetic spin-1/2 XXZ chain under an adiabatic demagnetization process using the quantum transfer-matrix technique and non-linear integral equations. The limiting case of the Ising…
We consider the exactly solvable spin-1/2 $XX$ chain with the three-spin interactions of the $XZX+YZY$ and $XZY-YZX$ types in an external (transverse) magnetic field. We calculate the entropy and examine the magnetocaloric effect for the…
We consider the Grueneisen parameter and the magnetocaloric effect near a pressure and magnetic field controlled quantum critical point, respectively. Generically, the Grueneisen parameter (and the thermal expansion) displays a…
The presence of a quantum critical point (QCP) can significantly affect the thermodynamic properties of a material at finite temperatures T. This is reflected, e.g., in the entropy landscape S(T, r) in the vicinity of a QCP, yielding…
We have measured and calculated the magnetocaloric effect in macroscopic samples of oriented high-spin molecular clusters like Mn12 and Fe8 as a function of the temperature and both the intensity and the sweeping rate of the applied…
Magnetic properties of the ferrimagnetic mixed spin-(1/2,S) Heisenberg chains are examined using quantum Monte Carlo simulations for two different quantum spin numbers S = 1 and 3/2. The calculated magnetization curves at finite…
The isothermal entropy change and the adiabatic temperature change for the exactly solved spin-1/2 Fisher's super-exchange antiferromagnet are rigorously calculated in order to examine magnetocaloric properties of the model in a vicinity of…
The thermodynamic and magnetocaloric properties of a generalized spin-$(1/2,s)$ Fisher's super-exchange antiferromagnet are exactly investigated by using the decoration-iteration mapping transformation. Besides the critical temperature,…
The Gr\"{u}neisen ratio $\Gamma$ and its magnetic analog, the magnetic Gr\"{u}neisen ratio $\Gamma_H$, are powerful probes to study the nature of quantum phase transitions. Here, we propose a Gr\"{u}neisen parameter, the rotational…
In this work we present a theoretical investigation into an antiferromagnetically coupled spin system, specifically ${\rm Cu}_{3}-X$ ($\mathrm{X=As,Sb}$), which exhibits an isosceles triangular configuration or slightly distorted…
The magnetocaloric effect is studied at the transition to saturation in the antiferromagnetic spin-1/2 Heisenberg model on the simplest two-dimensional lattices, namely the square and the triangular lattice. Numerical results are presented…
We study an integrable spin chain with an alternating array of spins S=1/2, 1 in external magnetic fields using the Bethe ansatz exact solution. The calculated magnetization possesses a cusp structure at a critical magnetic field H=H_{C},…
At a generic quantum critical point, the thermal expansion $\alpha$ is more singular than the specific heat $c_p$. Consequently, the "Gr\"uneisen ratio'', $\GE=\alpha/c_p$, diverges. When scaling applies, $\GE \sim T^{-1/(\nu z)}$ at the…
Recent research dealing with magnetocaloric effect (MCE) study of antiferromagnetic (AFM) low dimensional spin systems have revealed a number of fascinating ground-state crossover characteristics upon application of external magnetic field.…