Thermal properties of NdIn3

Abstract

The specific heat of NdIn, in the temperature range 2.3 t o 27 K and in the magnetic field up to 5 T as well as the thermal expansion between 1.5 K and room temperature are measured. The low-temperature behaviour of NdIn, is governed by the energy gap in the spin wave spectrum. The specific heat at the antiferromagnetic transition reveals anomalously large critical exponents.It is shown that the specific heat anomaly a t T N contains contributions from two closely lying transitions. The influence of the magnetic field on the energy gap, on the first-order transitions found in the antiferromagnetic state, and on the NBel peak is studied. Thermal properties in the paramagnetic state are analyzed basing on the available CF data.An NdIn, werden im Temperaturbereich 2,3 bis 27 K und im Magnetfeldern bis 5 T die spezifische Warme und im Bereich zwischen 1,5 K und Raumtemperatur die thermische Ausdehnung gemessen. Das Tieftemperaturverhalten wird von einer Energieliicke im Spinwellenspektrum bestimmt. Die spezifische Warme wird in der N l h e der antiferromagnetischen Ordnung durch ungewohnlich hohe kritische Exponenten beschrieben. Es wird gezeigt, daO die Anomalie in der spezifischen Warme bei T N aus zwei nah beieinander liegenden Ubergangen besteht. Untersucht wird der EinfluB des Magnetfeldes auf die Energieliicke, die beiden ubergange 1. Art im antiferromagnetischen Ordnungszustand und auf den NBel-Peak. Die thermischen Eigenschaften im paramagnetischen Zustand werden auf der Grundlage der zur Verfiigung stehenden Kristollfeldparametern analysiert.

Magnetic phase diagram of ErIn3

“…Indeed, the magnetic field applied along the (001)-axis separates these two transitions distinctly. A similarly strong divergence has been previously found in HoSb 112 to 141 and NdIn, [15]. It has been shown [16, 171 that a necessary condition for the appearance of such strong divergence is an accidental, nearly sixfold degeneracy of the crystal-field ground state.…”

Magnetic phase diagram of NdIn3

“…4). In zero magnetic field both transitions are separated by about 10 mK [2]. The line of the first metamagnetic transition (1) to (4) belong to the first to fourth magnetic transition, respectively splits at the point A (2.5 K, 8.0 T) in two transitions lines which end at T,, and Z 2 , respectively.…”

“…The line of the first metamagnetic transition (1) to (4) belong to the first to fourth magnetic transition, respectively splits at the point A (2.5 K, 8.0 T) in two transitions lines which end at T,, and Z 2 , respectively. The low-field part (up to 5 T) of the magnetic phase diagram has been established on the basis of the previously reported heat capacity data [2].…”

“…NdIn, crystallizes in a cubic AuCu,-type structure in which Nd3+ ions form a simple cubic lattice. The compound orders antiferromagnetically at TN = 5.90 K [l] through a continuous transition, but with an anomalously strong divergence of the associated heat capacity (critical index CI = 1) [2]. It has been shown [2] that this behaviour IS due to the occurrence of an extra transition at TE, = 5.89 K, just below the Nee1 point.…”

“…In this paper we propose a magnetic phase diagram of Ndln, in a magnetic field applied along the (001) axis. The diagram is built on the basis of the magnetization and longitudinal magnetoresistance and also on previously reported heat capacity data [2].…”