Jubilee scientific session dedicated to the 100th anniversary of the birth of Prof. Milko Borissov, Full Member of the Academy, was held online on 18 October 2021. It was organized by the Institute of Solid State Physics at BAS (ISSP-BAS) and the Union of Physicists in Bulgaria.

The Forum was opened by the Director of ISSP, Prof. Hassan Shamati. Recollections of the lecturer, teacher and organizer were told by Prof. Ivan Lalov, Corr. Mem. Lozan Spassov and Prof. Nikola Sabotinov, Full Member of the Academy.

For Prof. Lalov, Acad. Milko Borissov is the founder of the Department of Solid State Physics at the Faculty of Physics, Sofia University, where future researchers are trained for the needs of the ISSP. He is one of the greatest promoters of engineering physics who strived to create specialists needed for the nuclear power industry and quantum electronics in Bulgaria. He is the author of a number of textbooks and manuals for undergraduate physicists and for secondary school. He has initiated the introduction of modern physics and the modern concept of teaching physics into the curriculum. He is the organizer of the International School of Condensed Matter Physics, which is still held today.

For Corr. Mem. Lozan Spassov, Milko Borissov initiated research on the physics of surface-acoustic waves and their use in acousto-electronic devices. He set up a general training programme and organised an evening postgraduate course on “Physics of Acoustic Waves” for industrial specialists. He devoted the last 20 years of his life to the establishment and development of the Acoustoelectronics Laboratory at ISSP.

For Acad. Nikola Sabotinov, he was the long-standing director of the Institute of Solid State Physics who supported scientists so that they could realize their scientific ideas and protect their intellectual property.