Growth, Crystal Structure and Magnetic Characterization of Zn-Stabilized CePtIn₄

Abstract

The growth and characterization of CePtIn4, stabilized by 10% Zn substitution for In, is reported. The new material is orthorhombic, space group Cmcm (No. 63), with lattice parameters a = 4.51751(4) Å, b = 16.7570(2) Å, and c = 7.36682(8) Å, and the refined crystal composition has 10% of Zn substituted for In, i.e. the crystals are CePt(In3.6Zn0.1)4. Crystals were grown using a self-flux method: only growths containing Zn yielded CePtIn4 crystals, while Ce3Pt4In13 crystals formed when Zn was not present. Anisotropic temperature-dependent magnetic susceptibilities for single crystals show that Zn-stabilized CePtIn4 orders magnetically at ~1.9 K. High-temperature Curie-Weiss fits indicate an effective moment of ~2.30 µB/ Ce and a directionally averaged Weisstemperature of approximately -9 K. Specific heat data shows a peak consistent with the ordering temperature seen in the magnetic susceptibility data. Zn-stabilized CePtIn4 is metallic and displays no superconducting transition down to 0.14 K.

Study on CePtIn4 grown in a platelet-like morphology

“…[14] for the needle-like crystals of CePtIn4. However, the refined lattice parameters are somewhat larger than those derived for the N-type crystals (with the unit cell volume smaller by about 1.6%) [14], and more similar to the values reported recently for Zn-stabilized CePtIn4 (having the unit cell volume smaller by about 0.5% with respect to that of the P-type crystals) [17]. In the present case, In flux was used for crystal growth, so no occupational substitution of any foreign atom can occur.…”

“…At the onset of the AFM ordering, a sharp drop in ρ(T) is seen (see the inset to Figure 4) that occurs due to reduction in spin disorder scattering. Interestingly, no similar feature was seen before for neither for the N-type crystals nor the Zn-stabilized crystals of CePtIn4 at their respective AFM phase transitions [14,17].…”

“…Since the unit cell dimensions of the P-type crystals are slightly larger than those of the N-type one, also the interatomic distances are somewhat longer in the former modification of CePtIn4 (see Table 4). Remarkably, the Neel temperature of the P-type CePtIn4 is higher than TN = 1.65 K determined before for the N-type modification of the compound [14] and TN = 1.9 K reported for the Zn-containing crystals [17]. In order to confirm the AFM character of the ordered state, isothermal magnetization measurements were carried out at temperatures below and above TN.…”

“…Indeed, as can be inferred from the upper inset to Figure 3, the sample exhibits a pronounced maximum in χ(T) at TN = 2.3 K, characteristic of AFM phase transition. Remarkably, the Neel temperature of the P-type CePtIn4 is higher than TN = 1.65 K determined before for the N-type modification of the compound [14] and TN = 1.9 K reported for the Zn-containing crystals [17]. In order to confirm the AFM character of the ordered state, isothermal magnetization measurements were carried out at temperatures below and above TN.…”