A memory of Ludvík Smrčka

The recently deceased Ing. Ludvík Smrčka DrCs, an excellent researcher and a friend, as remembered by his co-workers Pavel Středa, Petr Vašek, Pavel Svoboda and Jan Kočka. Ludvík Smrčka left an indelible mark on their professional and private lives.

Ludvík Smrčka considerably influenced both our professional and private lives. Two of us (Pavel Středa, Petr Vašek) met him first as early as in 1961 at an international youth summer camp at Zruč nad Sázavou, where he was working as a camp leader. This was during our last summer vacation at the secondary school and we were considering what we should do in the future. He studied at the Faculty of Technical and Nuclear Physics of the Czech Technical university (ČVUT) and the conversations about physics with him convinced us to start studying at the same faculty. This was where we met him again; this time he was a lecturer on field theory. He arranged for us research assistants posts at the Institute of Solid State Physics (now a section of the Institute of Physics at “Cukrovarnická”), where he was working on his dissertation. The dissertation dealt with experimental issues; he was weighting vacancies. But as the shipment of the devices he had ordered arrived only after the completion of the dissertation, he came to understand that it was not the right time for experimental career to be pursued and decided to switch to theory. As a candidature thesis (Candidate of Science, a scientific degree in former Czechoslovakia), he did calculations of the aluminium electron structure and defended the thesis in 1970. At that time, together with Ludvík Smrčka, we were already members of a work group established by dr. Karel Míšek at the Department of Metals of the former Institute of Solid State Physics (ÚFPL) . From the very beginning, the group, consisting of 2 theorist (Smrček, Středa) and 2 experimentators (Vašek, Svoboda), was characterised by a very close cooperation, which was due to our, including dr. Míšek‘s, being cooped up in one room for many years. The underlying professional topic of the group was the research in physical properties of solids, primarily metals and semimetals, under low temperatures.

In the 1980‘s, when the original ÚFPL had already been part of today‘s Institute of Physics, the whole field of solid state physics was significantly influenced by the newly discovered macroscopic quantum phenomena, quantum Hall effect (KHJ) and later also high-temperature superconductivity. At that time, Ludvík Smrčka was exploring quantum theory of electron transport in magnetic fields and it was at his instigation that our whole group began to concentrate on these new phenomena. One of us (Středa) learned the basics of quantum theory from Ludvík to such an extend that it allowed him to formulate a theory of quantum Hall effect. The exploration of quantum Hall effect was later joined by experimentators who, using the MBE technology, acquired suitable semiconductor structures.

A key aspect of the quantum Hall effect and the related phenomena is the charge transport in two-dimensional electron systems. The intensive development in this discipline as seen at the end of the 1980‘s inspired Ludvík to implement arguably the most significant coordination project of his career. In October 1990, he launched the Department of Semiconductors at the FZU and established a new Surface and Interface Department. He became the head of the latter, and we followed him as team members. Under his leadership, a new workplace with top technology and experimental instrumentation was created. Then, apart from the installation of a modern MBE apparatus, he also set up the laboratory of electron lithography. The creation of the laboratory was part of a large project entitled “Nanotechnology Centre and Nanoelectronics Materials” with the participation of several departments of the FZU (responsible researcher J. Kočka), and where Ludvík was in charge of the project‘s spintronic part. The Surfaces and Interfaces Department gradually evolved into the present day Department of Spintronics and Nanoeletrconics. Even after Ludvík handed over the management of the department to his younger successors, he would contribute to the department‘s scientific programme until his last moments.

We mentioned at the beginning that our group has shared one office throughout the many years despite the fact that the room has belonged to four various departments under two different Institutes of the Academy of Sciences owing to numerous reorganisations. The latest reorganisations in the last few years have spread us around the Institute of Physics; one of us (Svoboda) left the Institute but Ludvík returned to the same room at the end of his career and worked there to the end of his days.The complete list of Ludvík‘s publications, grants and other expert activities can be viewed at the following website ústavních stránkáchWe would like to mention here just some of the personal observations and memories of our cooperation in the last more than 50 years. As said before, Ludvík – in spite of his being a theorist – had a very close relationship to experimental research and he held a view that an experiment is the corner stone of the entire physics. In our work group, this was reflected by the fact that he would inspire and sometimes even task experimentators with assignments in their work. This could be seen perhaps the most in our long-term cooperation with the CNRS Laboratory of Magnetic fields in Grenoble. This project was Ludvík‘s affair of the heart. Between 1996 and 2012, he proposed and carried through 21 projects which allowed us to study various types of semiconductor structures prepared by our technologists at the FZU using their unique magnets with magnetic fields of up to 30 T. Once a year or sometimes even twice, we set off on a journey by car to Grenoble for a week, and these trips - during which we took turns behind the wheel and, in the first years, also slept in the car at parking lots, remain etched into the memories of the participants. Also, we can‘t forget all the stressful situations during experiments, the beautiful view from the window of a guest room at the premises of the laboratory and the trips we took around Grenoble.

Numerous memories are also connected with leisure time activities that we and many of our colleagues indulged in with Ludvík. These were mostly linked with the holiday houses of the ÚFPL and later of the FZU in Horní Rokytnice. It is hard to fully appreciate the influence that these places have on establishing and building personal relationships among the co-workers of the FZU. Staying at the holiday houses, doing common maintenance and taking skiing trips have brought together several generations of employees and their families. This was where life-long friendships that reached far beyond the workplace were made. We played various sports together, first it was basketball and, later, mainly tennis. It was a game of tennis with friends at the tennis court of the Institute at “Cukrovarnická” that was the last thing he experienced in his life. Together we sometimes went on holidays, we celebrated New Year‘s Eve as well as our round anniversaries. In all that, Ludvík will be greatly missed.

Pavel Středa, Petr Vašek, Pavel Svoboda, Jan Kočka