ORIGINAL PAPER Signature of Ferromagnetic Phase at Low Temperature in Low-Doped La 0.88 Ca 0.12 MnO 3 Single Crystal Tejas M. Tank 1,2 & M. Prajapat 1 & D. S. Rana 1 & A. Bodhaye 3 & Ya. M. Mukovskii 4 & S. P. Sanyal 2 Received: 5 January 2019 /Accepted: 5 March 2019 # Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract The confirmation of ferromagnetism at low temperature in a low-doped manganites system is always debatable. It is for the first time, electrical, magnetic, and thermal properties have been measured for manganites single crystal of La 0.88 Ca 0.12 MnO 3 by using a floating-zone method. The electrical resistivity shows a perceptible change of resistance at a low temperature which can be viewed as a signature of the ferromagnetic phase. The ferromagnetic phase of the investigated La 0.88 Ca 0.12 MnO 3 single crystal with Curie temperature of T C = 120 K which is in closed agreement with ac-susceptibility measurement. An analysis of the specific heat suggests the transition peak (T P ) coincides with the T C and attains 1.2 J mol −1 K at 116 K. The magnetoresistance (MR) and temperature coefficient of resistance (TCR) were found to be 69% and 10% respectively, which expands its subtle potential for applications in spintronics and thermistor. Keywords Manganites . Single crystal . Crystal growth . Magnetic properties . Specific heat 1 Introduction The perovskite-based manganese oxides, RE 1-x A x MnO 3 , (RE = La 3+ , Pr 3+ , Nd 3+ , etc., A = Ca 2+ , Sr 2+ , Ba 2+ , etc.) have been motivated by the observation of colossal magnetoresistance (CMR) in these materials. This fundamental mechanism of the CMR phenomenon is well explained by double exchange (DE) mechanism, Jahn–Teller (JT) distortions. A wide variety of properties in CMR materials were studied intensively by several factors such as mixed valence, charge ordering, ionic size mismatch, Mn–O bond lengths, Mn–O–Mn bond angles, oxygen stoichiometry, and RE and Mn-site doping [1–4]. Depending on the bandwidth of the e g electron, the manganite system, La 1-x Ca x MnO 3 (LCMO) which exhibits transition be- low room temperature is an intermediate bandwidth system. Among all perovskite manganites, there has been much inter- est in the close interplay between structural, electrical, mag- netic, and thermal properties in La 1-x Ca x MnO 3 compounds since few decades [5, 6]. The properties of CMR manganites strongly depend on the doping level “x.” Schriffer et al. had reported ferromagnetic behavior for La 1-x Ca x MnO 3 manga- nites in the 0.2 ≤ x ≤ 0.5 doping system, while the low doping regime is far from being explored [7]. The La 1 − x Ca x MnO 3 compound exhibits both metallic and ferromagnetic in 0.20 < x < 0.50 doping region, as the interactions are dominated by DE mechanism. Though, La 1 − x Ca x MnO 3 , among 0.10 < x < 0.20, has a ferromagnetic insulating ground state. This unpredicted coexistence of ferromagnetic and insulating be- havior appears to contradict the conventional double and superexchange models [8]. In the region of interest for this paper, i.e., x = 0.12, the reported observations for x = 0.1 are not always reliable. Most studies of La 1-x Sr x MnO 3 single crystals performed using optimally low doped with x = 0.1 were carried out by Lofland et al. [9], Kumagai et al. [10], and Paraskevopoulos et al. [11]. They found the nature of the ferromagnetic and insulating phase, while some measurements interpreted it to be in the * Tejas M. Tank tejast@iiserb.ac.in 1 Department of Physics, Indian Institute of Science Education and Research, Bhopal, Madhya Pradesh 462 066, India 2 Department of Physics, Barkatullah University, Bhopal 462 026, India 3 Department of Physics, St. Vincent Pallotti College of Engineering & Technology, Nagpur 400 002, India 4 National Science and Technology University, (MISIS), Leninskii Prospekt 4, Moscow 119 049, Russia Journal of Superconductivity and Novel Magnetism https://doi.org/10.1007/s10948-019-5075-7