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CsDy(MoO4)2 belongs to the family of binary alkaline rare-earth molybdates, with detectable low-temperature structural phase transitions, caused by the cooperative Jahn-Teller effect. Magnetocaloric studies of a single crystal of CsDy(MoO4)2 have been performed in the temperature range from 2 K to 18 K in magnetic fields up to 7 T applied along the crystallographic a axis. The maximum value of the isothermal entropy change is about 8 J/(kgK) and was achieved already in the fields above 2 T. The observed results suggest that the studied system can be used as a magnetic refrigerant at helium temperatures. [ABSTRACT FROM AUTHOR]

We report on the basic physical properties of a novel CeCo0.715Si2.285 compound, mainly its rich magnetic phase diagram. The compound crystallizes in the I-4m2 space group structure with extremely elongated unit cell (a = 4.12 Å, c = 32.84 Å). In a zero magnetic field it orders antiferromagnetically at TN = 10.5 K with another order-to-order transition at 9.5 K. Under application of a magnetic field along the c-axis it manifests numerous magnetic transitions in small fields (B < 500 mT), resembling the so-called "devil's staircase" systems. Above 1 T the magnetization is almost constant up to 14 T (maximum magnetic field applied within our study) but considerably reduced (0.3 μB/Ce) with respect to the free Ce3+ ion. After removing the applied field, however, the high field state remains unchanged to be removed in negative fields. The compound also exhibits strong hysteresis of magnetization with respect to varying temperature or magnetic field. For fields applied along the a-axis typical behavior for the hard axis in the material with uniaxial anisotropy is observed. [ABSTRACT FROM AUTHOR]

Recently a new wave of interest in physics of RCo2 compounds has been boosted by reports on unusual magnetic short range order configurations in the heavy rare-earth RCo2 ferrimagnets in paramagnetic state. The newly observed phenomenon called parimagnetism consists in a short-range antiferromagnetic coupling between small ferromagnetic Co clusters and the nearest rare-earth moments. This paper is devoted to results of our experimental can be found in literature. Detailed magnetization. AC susceptibility, specific heat and electrical resistivity measurements revealed two magnetic phase transitions at 4.6 and 3.6 K, respectively. The anomalies connected with the transitions are strongly dependent 011 magnetic field and hydrostatic pressure. The AC susceptibility anomaly connected with the onset of parimagnetism has been found at Tf = 35 K. Contrary to other heavy rare-earth RCo2 counterparts Tf of TmCo2 is entirely pressure independent. [ABSTRACT FROM AUTHOR]

We report on synthesis and anisotropic physical properties of URhIn5. High quality single crystals were grown from In self-flux. The compound undergoes a second-order phase transition into an antiferromagnetic state at TN = 98 K. The transition is magnetic field independent up to 9 T. An increase of the resistivity ρ with j along the [100], [110] and [001] tetragonal axis indicates a spin-density-wave induced order with the gap opening first along the [001] direction. The magnetic susceptibility US χ= M/H exhibits a strong anisotropy. Above T = 200 K, US(T) follows the Curie-Weiss law with the effective moment of μeff = 3:71 μB/U and the Weiss temperatures of θ[100]p= -900 K and θ[100]p= -500 K for H k [100] and H k [001], respectively. The characteristic Kondo-like temperature for URhIn5 yields TK = 125 K. [ABSTRACT FROM AUTHOR]

A new configuration of cobalt magnetic moments with respect to rare-earth ones on local level, named as parimagnetism, surviving above the Curie temperature was determined few years ago for ErCo2. Occurrence of parimagnetism has recently been confirmed also for HoCo2. In this paper we present results manifesting considerable composition and hydrostatic-pressure influence on characteristic temperatures of magnetism in Ho(Co1-xSix)2 compounds and draw a preliminary scenario analyzing the exchange interactions involved. [ABSTRACT FROM AUTHOR]

The thermal conductivity of the quasi-one-dimensional S = 5/2 Heisenberg antiferromagnet CsMnCl3·2H2O with the intrachain interaction J/kB = 3 K was experimentally studied at temperatures from 2 to 25 K. The data analysis performed within the Debye model with the relaxation-time approximation unambiguously indicates the presence of the scattering of phonons on magnetic subsystem. [ABSTRACT FROM AUTHOR]

UCoGe is an archetype of coexisting weak itinerant 5f-electron ferromagnetism (TC ~ 3 K,μs = 0:03μB/f.u.) and superconductivity (TSC ~ 0:6 K) at ambient pressure. The Ru substitution for Co leads to an initial sharp increase of the TC up to the maximum of TC = 8:5 K for x = 0:12, increase of spontaneous magnetic moment and suppression of superconductivity. We have grown the UCo0:88Ru0:12Ge single crystal and studied magnetization along the principal crystallographic axes. To see the microscopic background of these findings we performed a polarized neutron diffraction experiment on D3 diffractometer in ILL. We have found that the Co and U moments are parallel in UCo0:88Ru0:12Ge, in contrast to the antiparallel configuration in UCoGe. This is probably the reason of the spontaneous magnetization increase with Ru doping. [ABSTRACT FROM AUTHOR]

We report on the investigation of recently discovered heavy fermion compounds within the Ce-Pd-In system. Single crystals of CenPdmIn3n+2m (n = 2; 3; 5; m = 1; 2) and Ce4Pd10In21 were synthesized from In-flux. Specific heat measurements of the multiphase CenPdmIn3n+2m system revealed a superconducting transition at Tc = 0:69 K arising from Ce2PdIn8 and another, magnetic transition at Tm = 1:67 K arising from either Ce3PdIn11 or Ce5Pd2In19. Low-temperature data of Ce4Pd10In21 display ferromagnetic long-range order below 0.8 K. [ABSTRACT FROM AUTHOR]

Single crystals of YbPt2Si2 and Yb2Pt3Si5 have been prepared by solvent growth method with Sn flux, characterized by X-ray diffraction and by EDX microprobe analysis and investigated by measurement of magnetization, specific heat and electrical resistivity as functions of temperature and magnetic field. YbPt2Si2 (Yb2Pt3Si5) crystalizes in the tetragonal CaBe2Ge2-type (orthorhombic U2Co3Si5-type) structure. Both compounds exhibit metallic resistivity behavior without visible anomaly, which could be connected with onset of magnetic ordering. Neither the specific heat shows any sign of magnetic ordering down to 0.5 K. The corresponding temperature dependences of the magnetic susceptibility of both compounds behave qualitatively similar, which is reminiscent of spin fluctuation behavior: a broad maximum at high temperatures, a shallow minimum at lower temperatures, followed by an upturn with further cooling the crystal, which can be suppressed by applying a sufficient magnetic field. The rather low values of the γ-coefficients of the specific heat (~ 25 ÷ 35 mJ∙mol∙K-2) do not support the mixed valence scenario discussed in literature for YbPt2Si2. [ABSTRACT FROM AUTHOR]

The short-range parimagnetic configurations, observed in the heavy rare-earth RCo2 compounds in paramagnetic range far above the Curie temperature TC, consist in formation of ferromagnetic cobalt clusters antiferromagnetically coupled to the neighboring R magnetic moments. The characteristic temperature of the onset of parimagnetism Tf is very sensitive to changes of external conditions like pressure or composition. The pressure coefficients ∂Tf/∂p and ∂TC/∂p are comparable, indicating a close connection of underlying mechanisms. Our recent measurements indicate systematic evolution of the pressure coefficients with spanning the rare-earth series from Dy through Tm in RCo2 with a specific case TmCo2. [ABSTRACT FROM AUTHOR]

The results of direct measurements of the magneto-caloric characteristics Δ Tad and the indirect determination of Δ Sm of pure Gd around the Curie temperature and of the FeMnP0.45As0.55 and Ni45Co5Mn31Ga19 intermetallics in the vicinity of the first order magnetic and structural phase transitions are presented and discussed. A pronounced temperature and field dependence of the first order transitions in the studied materials manifests restrictions applying these materials in magnetic refrigeration techniques. An effective use of the Ericsson and the Brayton refrigeration cycles with FeMnP0.45As0.55 in the role of a refrigerant is discussed. [ABSTRACT FROM AUTHOR]

The thermal conductivity of CsGd(MoO4)2 has been studied in the temperature range from 2 to 50 K in zero magnetic field. The analysis of the data performed within the Debye model with the relaxation-time approximation revealed the presence of the scattering of phonons by critical fluctuations. The behaviour of phonon mean free path at the lowest temperatures is discussed. [ABSTRACT FROM AUTHOR]

In the presented work we report electrical, magnetic and thermal properties of EuB6- xCx single crystals with an estimated value of x ˜ 0.07. Our studies reveal an antiferromagnetic phase transition at TN ˜ 6.7 K. Electrical resistivity at zero magnetic field shows a pronounced resistivity maximum at TM ˜ 7 K, just above the antiferromagnetic phase transition temperature. With increasing applied magnetic field the maximum moves to lower temperature and becomes totally suppressed at the field of 9 T. Observed magnetoresistance is negative in the whole studied temperature range 2-20 K, yielding a ratio of ?(0 T, 7 K)/?(9 T, 7 K) ˜ 2.5. The origin of such magnetoresistance is associated with formation of mixed magnetic structure in the system due to fluctuation of carbon concentration. [ABSTRACT FROM AUTHOR]

CsDy(MoO4)2 belongs to the family of binary alkaline rare-earth molybdates, with detectable low-temperature structural phase transitions, caused by the cooperative Jahn-Teller effect. Magnetocaloric studies of a single crystal of CsDy(MoO4)2 have been performed in the temperature range from 2 K to 18 K in magnetic fields up to 7 T applied along the crystallographic a axis. The maximum value of the isothermal entropy change is about 8 J/(kgK) and was achieved already in the fields above 2 T. The observed results suggest that the studied system can be used as a magnetic refrigerant at helium temperatures. [ABSTRACT FROM AUTHOR]

Recently a new wave of interest in physics of RCo2 compounds has been boosted by reports on unusual magnetic short range order configurations in the heavy rare-earth RCo2 ferrimagnets in paramagnetic state. The newly observed phenomenon called parimagnetism consists in a short-range antiferromagnetic coupling between small ferromagnetic Co clusters and the nearest rare-earth moments. This paper is devoted to results of our experimental can be found in literature. Detailed magnetization. AC susceptibility, specific heat and electrical resistivity measurements revealed two magnetic phase transitions at 4.6 and 3.6 K, respectively. The anomalies connected with the transitions are strongly dependent 011 magnetic field and hydrostatic pressure. The AC susceptibility anomaly connected with the onset of parimagnetism has been found at Tf = 35 K. Contrary to other heavy rare-earth RCo2 counterparts Tf of TmCo2 is entirely pressure independent. [ABSTRACT FROM AUTHOR]

In the presented work we report electrical, magnetic and thermal properties of EuB6- xCx single crystals with an estimated value of x ˜ 0.07. Our studies reveal an antiferromagnetic phase transition at TN ˜ 6.7 K. Electrical resistivity at zero magnetic field shows a pronounced resistivity maximum at TM ˜ 7 K, just above the antiferromagnetic phase transition temperature. With increasing applied magnetic field the maximum moves to lower temperature and becomes totally suppressed at the field of 9 T. Observed magnetoresistance is negative in the whole studied temperature range 2-20 K, yielding a ratio of ?(0 T, 7 K)/?(9 T, 7 K) ˜ 2.5. The origin of such magnetoresistance is associated with formation of mixed magnetic structure in the system due to fluctuation of carbon concentration. [ABSTRACT FROM AUTHOR]