Igor Olegovich Troyanchuk (b. in Poltava, Ukraine, 27.11.1956 – 15.09.2018), physicist. Corresponding Member of the National Academy of Sciences of Belarus (2004), Doctor of Physico-Mathematical Sciences (1991), Professor (2003).
Scientific works in the field of studying the magnetic and electrotransport properties of magnetically ordered media, the development of the technology of ceramic materials, ferrites and their practical application. He developed the concept of orbital phase separation in magnetic semiconductors, revealed the nature of magnetic transformations leading to the effect of "enormous" magnetoresistance. He established that the superexchange magnetic interactions through anions in magnetic semiconductors significantly exceed the exchange interactions through charge carriers. He discovered a series of metal-dielectric phase transformations, the nature of which is associated either with electron ordering or with a change in the spin state of magnetic ions. He studied the family of magnetic semiconductors with a large magnitude magnetoresistive effect. Discovered an intergranular magnetoresistive effect in oxides with a perovskite and pyrochlore structure. Using high pressure technology, he obtained a number of metastable compounds with unusual magnetic and electrical properties. He developed a technology for producing highly coercive needle barium hexaferrite for magnetic recording of information on flexible media and a number of high-frequency and magnetic-hard magnetic materials. Developed methods for lowering the sintering temperature of ceramic materials, which is important for improving their performance and miniaturizing devices.
Author of more than 400 scientific papers, incl. 2 monographs.
State Prize of the Republic of Belarus in 2004 for researching the magnetic structure and physical properties of multicomponent systems with transition and rare-earth elements and the development of new magnetic materials, the creation and production of elements and devices of electronic equipment.