Research Projects

Exploration of quantum magnetic phases in materials is very important both from the viewpoint of basic physics and technological applications and is being actively pursued by condensed matter physicists in recent years. Initially, this type of investigations was carried out on transition-metal oxides. In these systems, the magnetic ground states are independently determined by the spin quantum number and experimental signatures of novel quantum ground states like quantum spin liquid, spin ice, spin – ½ ground states, low dimensional magnetism etc., are very well established. However, with time, the field is extended to 4d, 5d as well as 4f based magnetic materials. Magnetic insulators provide a fertile background to explore the possibility of novel quantum magnetic phases. In this context, rare-earth (R) based oxides with strong spin orbit coupling, geometric frustration and anisotropic exchange interaction, can also give rise to the diverse novel quantum phases. The research this area is continuously evolving and finding new exhibiting these kind exotic properties is a very important area in current context; as new technology relies on new materials. Hence, the main focus of this research project is a thorough investigation of different rare-earth oxide family, in which the magnetic properties are solely dependent on the R ion and also on how they are arranged in different lattice geometries. Investigation will be carried out on series where strong magnetic frustration results in novel quantum spin liquid state and strong crystal field effects leads to a magnetic ground state associated with low effective spin. Additionally, geometrical frustration is another way to induce magnetic frustration which helps in realization of diverse exotic magnetic ground states. This will be studies on new family rare earth oxides. Furthermore, field induced exotic quantum magnetic phases and insight about low dimensional magnetic ground state at low temperatures will be explored on other rare-earth oxide series. These studies will present an idea about field induced exotic quantum magnetic phases at low temperatures on relatively unexplored rare-earth oxide series will also shed further insight about low dimensional magnetic ground states. The above goals will be achieved by preparing the samples (mentioned in the objective section) by using solid state ceramic route. The characterization of the prepared samples will be carried out using powder X-Ray Diffraction and FESEM. Raman spectroscopic studies will also be done. Temperature, time, magnetic field dependent magnetization data will be collected by the Magnetic Property Measurements System. Heat capacity measurement will be performed using Physical Property Measurements System. For probing the state at very low temperatures, magnetic and heat capacity measurement below 1.8 K using He-3 set-up will be done. Additionally, density functional theory calculations to calculate the values of magnetic exchange interaction, will be carried out. To investigate the change in electronic band structure, study using photoelectron spectroscopy will be carried out. Presence of any structural change, if present in the sample, will be probed through temperature dependent x-ray diffraction measurement. As per our requirement, to explore the changes in magnetic structure across the phase transitions, temperature dependent neutron diffraction measurement will be done. Additionally, other microscopic probes like muon spin resonance (muSR) and in-elastic neutron scattering will be carried out as these measurements can play an impactful role in confirming above-mentioned novel ground states. The principal investigator of the project is well experienced in sample preparation and characterization, along with the investigation of the physical properties of rare earth-based oxides. The grant from ANRF will help to extensively work in the area of quantum magnetism at IIT, Mandi.