Anita Eka Putri, a student of the Materials Science Doctoral Program at the Faculty of Mathematics and Natural Sciences, University of Indonesia (FMIPA UI), officially received her doctorate after successfully defending her dissertation entitled “Quantum Size Effect on Magnetic Properties of Parental Compound of Lanthanum Based High-Tc Superconductor Cuprates (La₂CuO₄)” in an open session held on Monday, June 30, at the Prof. Dr. G.A. Siwabessy Hall, FMIPA UI, Depok.
The doctoral promotion defense was chaired by Prof. Dr. rer. nat. Budiawan, the Chairperson of the Defense Committee and Vice Dean for Education, Research, and Student Affairs at the Faculty of Mathematics and Natural Sciences, University of Indonesia.
Anita was mentored by Dr. Budhy Kurniawan from the Department of Physics, Faculty of Mathematics and Natural Sciences, University of Indonesia, as her supervisor, and Dr. Isao Watanabe from the Nuclear Structure Research Group, RIKEN Nishina Center, Japan, as her co-supervisor. Thanks to her hard work and outstanding research results, Anita earned a Very Satisfactory distinction.
Anita’s research reveals how the magnetic properties of a superconducting material change when its size is reduced to the nanoscale, around 43 nanometers. “The material we focus on is La₂CuO₄ (LCO), the base material for high-temperature superconductors that play a crucial role in advanced electronics and computer technology,” Anita explained.
The research results show that as the size of LCO particles decreases, their magnetic properties change drastically. For example, the Néel temperature, the temperature at which a material begins to exhibit specific magnetic properties, drops from around 300 Kelvin (27°C) to around 90 Kelvin (-183°C). Even very small particles exhibit a different magnetic property, namely weak ferromagnetism, which remains stable at room temperature. This finding is crucial for the development of future technologies.
Additionally, Anita discovered two competing magnetic properties in the material, something previously unseen in larger particles. To study this phenomenon, she used advanced instruments such as the SQUID magnetometer and muon spin relaxation (μSR), which allows for the observation of magnetic properties down to the atomic level.
Anita hopes that the results of her research can encourage the advancement of domestic technology, especially in the field of more efficient and energy-saving superconductors.
“I hope this research can pave the way for the development of more efficient superconductor technology and can drive innovation in various fields, such as electronics, electric vehicles, and future magnetic systems,” he said.
This research opens up huge opportunities for innovation across a wide range of modern technology sectors, including miniaturized chips, smart sensors, seamless electrical wiring, and magnetic systems for more advanced and environmentally friendly future vehicles.
