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Physics Department Physics

Remembering Stephan von Molnár

Main photo of Stephan von Molnár
Stephan von Molnár's photo
Professor Emeritus Stephan von Molnár of the Department of Physics, Florida State University, passed away on November 17, 2020 in Tallahassee, Florida. Stephan was a professor of physics at FSU from 1994 to 2013, and between 1994 and 2007, the director of the interdisciplinary Center for Materials Research and Technology (MARTECH). Stephan received his Ph.D in physics from the University of California, Riverside in 1965. From 1965 to 1993, he was a member of the Research Staff at the IBM Thomas J. Watson Research Center, where he also held positions as manager of the Cooperative Phenomena Group (1970 – 1989) and senior manager of the Novel Structure Physics Group (1989 – 1993). 

Stephan was a pioneer in the field of magnetic semiconductors and a trailblazer of spintronics, the technology of utilizing electron spin for electronic functionalities. His many accomplishments include: the conceptual development and experimental observations of magnetic polarons, realization of the first magnetic tunneling (field emission) device, experimental demonstration of a magnetically driven continuous insulator-metal transition, development of pure-phase transition metal-doped III-V diluted magnetic semiconductors, and invention of semiconductor Hall gradiometry and its applications in nanomagnetism and magnetic biosensing. 

A fine experimental physicist, Stephan was universally admired for his abilities in attaching fine gold wires to tiniest crystals (in the early days often while smoking a cigarette), making small devices (without using any lithography), and acquiring large volume of illuminating data (before automated instruments and LabView). His passion for experimental perfection and insistence of exceptional scientific rigor were legendary (and occasionally frustrating to his students).

An ardent music and theater enthusiast and an avid sports fan, Stephan was a proud season-ticket holder of both the Tallahassee Symphony and the Florida State Football. He was a goal-keeper on the Trinity College soccer team, and ventured in earnest into theater acting before finally decided to answer the calling in physics. His competitive fire in science research was matched only by that on a squash court, as many of us found out personally well into his 70s.

Always a true gentleman, Stephan treated everyone with the same warmth, respect, and willingness to lend a hand, be it a Nobel laureate or a graduate student he met for the first time. He always appreciated a clever physics idea or a good joke, no matter whom it came from. He applauded even the smallest progress and accomplishment of junior researchers; his encouragement, guidance, and support at critical junctures early in their careers are gratefully remembered by many.

He will be missed.
	

Colleagues and Students Remember

I have many fond remembrances of Stephan from our joint multidisciplinary university research initiative project that started in the mid-90’s and from writing joint proposals. He was always an entertaining, friendly and engaging presence, with a terrific sense of humor and perspective. All of us at UF looked forward to seeing him and enjoyed his company. He also came from a long background in industrial research, in his case at IBM, while I was an alumni of Bell Labs. That shared heritage gave us a sense of gratitude about the freedom available in academic research. Many of our contract reviews took place in the Florida Keys, mainly because our contract monitor was an avid diver. We always had a lot of fun with Stephan about his resemblance to Hemingway, and our proximity to that authors old house in Key West, as well as the annual Hemingway look-a-like contest held there. Stephan loved physics and always worked hard. I remember us holding some practice talks prior to an NSF site visit and he worked in some off-the-cuff jokes that came across in the actual presentations as spontaneous, but which he had carefully planned and practiced. A consummate pro. We’ll miss him very much.
 — Steve Pearton, professor of materials science and engineering, University of Florida, and MagLab affiliated faculty member 
	

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Stephan was a giant in our field. We lost a legendary figure. On a personal front, he was most supportive of me and had profound impact on my career when I started. I first met him in 1999 at Johns Hopkins. Stephan came to visit, as part of a NSF panel. I presented a talk on magnetoresistance studies in Bismuth, which he liked. We had great discussions then and afterwards. It was particularly encouraging for me as a fresh PhD to receive positive feedbacks from an external expert, not to mention someone of Stephan's stature. In the following years, we kept in touch. Often at conferences we would catch up. It was such a pleasure to talk to him. He was always sharp and kind, a great mentor. He was tremendously supportive when I started my faculty career, and continued even well after his retirement. For a while I didn't see him at conferences. But I was thrilled to run into him at the 2016 MMM in New Orleans and got a chance to talk to him at the boat reception. 

Looking back, even in my own faculty shoes today, the relationship I had with Stephan was quite unusual. I was never affiliated with him in any way. Yet out of his kindness he reached out and helped me so much along the way. He was a Santa Claus figure to me in multiple ways. I will miss him dearly.
 — Kai Liu, Professor and McDevitt Chair in Physics, Georgetown University 
	

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Photo from after Konstantinos's dissertation defense (2018 May)
From after Konstantinos's dissertation defense
May 2018
Prof. von Molnár retired before I joined Prof. Peng Xiong’s group in 2015. I first knew him from our weekly group meetings where he always asked questions. He planned to talk about magnetic polarons in early Nov and asked me to change the title (again) the day before he was in hospital. We had many interactions since I started my main PhD project on spin injection into semiconductors via chirality-induced spin selectivity (CISS). CISS was a small new field and he was very interested in introducing organic chiral molecules into semiconductor spintronics. We had many discussions of my data and theoretical explanations in the past three years. He would just call me every time he was excited about the new ideas. After the submission of our manuscript, it was rejected six times within nine months before it finally got accepted (ACS Nano 14, 15983 (2020)), only four days before he was in hospital. It was the very last project he was involved with and he always encouraged me to believe in the value of my work regardless of the editorial decisions. I am relieved that he was able to see the final positive outcome. He often asked what we do beyond research. I always liked to share my life stories with him and enjoyed his resonant laughs. He invited me to classical music concerts by Tallahassee symphony and we had many wonderful evenings at Ruby Diamond Concert Hall together. When I came across his name in books or heard the greetings from famous professors when I mentioned his name at conferences, it seems distant as he was a great scientist and had fantastic reputation in both industry and academia. But to me, he was such an amiable professor that especially cares about young people – students and early career scientists. I saw him last time on Nov 8 in the hospital. His eyes lit up as I walked in his room. He was very weak but asked what I have been doing recently and about my graduation plans. He promised to attend my dissertation defense in early spring 2021. He also said many good words for my future career. I will always miss him and carry on with his wishes and encouragements. — Tianhan Liu, PhD candidate, Physics Department, Florida State University

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I was a graduate student at the Department of Physics, Florida State University during 1998-2003. I was very fortunate to have worked under the supervision of Prof. Stephan von Molnár and Prof. Peng Xiong for four and a half years. Stephan was a perfect mentor. Without his incredible enthusiasm and deep insights, his teaching of many precious values, his patience and encouragements during my struggling times, and his generous help at critical stages of my career, I would not be able to enjoy the life of a scientist and an adviser to younger generations of graduate students. I’m also grateful to Stephan for giving me a challenging project at the very beginning, and for being supportive to pursue my own ideas during the final period of my graduate study. This helped a great deal to build my confidence, and gave me an opportunity to taste the joy of discovery. Stephan is my role model. He will be missed forever. 
 — Yongqing Li, Professor, Institute of Physics, Chinese Academy of Sciences, Beijing 
	

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I had the immense pleasure of meeting Steve upon joining IBM research in Yorktown Heights, New York. We hit it off from the very start, with Steve moving seamlessly from mentor to friend and collaborator, spanning many research projects across science and technology over the years. He was not only a close colleague, but someone I could trust and always turn to for advice. Steve’s deep scientific insights, extraordinary sense of humor, and unique ability to identify the critical issues underlying almost any problem made him truly one of a kind. He was instrumental in developing my own career at IBM, and someone with whom I spent many enjoyable evenings talking about research and life outside the lab (what little there was of it!). In particular, Steve was inspirational to the many students and postdocs at IBM who viewed him as a role model, and he strongly influenced their own careers. He will be sorely missed by all of us who owe him a great deal – we were lucky to have spent time with him and to learn from him.
 — David D. Awschalom, Liew Family Professor in Spintronics and Quantum Information, Deputy Dean of Pritzker School of Molecular Engineering, Director of Chicago Quantum Exchange, University of Chicago 
	

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I was upset to hear about Steve's death on 18th. He was an old friend - we first met at a conference in Geneva in 1973, and at a memorable IBM-France meeting in Rhiems a couple of years later. In 1976 I went to work with him and Fred Holtzberg at IBM . He was an amazingly skilled experimentalist, affixing tiny contacts with his oversized fingers 'fingerspritzen'. In many ways larger than life, I picked up phrases from him like 'C'mon Steve' that became 'C'mon Mike', a multipurpose expression of exasperation. A pioneer of magnetic tunneling long before the posse, Steve was passionate about science, solicitous of the wellbeing of his coworkers, a fine physicist and an enthusiastic American. We will miss him.
 — Michael Coey, Professor of physics, Trinity College, Dublin, Ireland 
	

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Photo where Jianhua Zhao was at Stephan’s house, taken in 2010
Jianhua Zhao was at Stephan’s house
2010
I knew Stephan in 2007 at the conference of Spintech IV, held in Hawaii. Since then, we started our cooperation and became good friends. In 2009, we started a joint project of “Magnetic and Spin-Dependent Electronic Properties of Semiconductor/Ferromagnet Hybrid Nanostructures”, granted by both NSFC and NSF. In the past 13 years, we have got some fruitful collaborative results. Stephan has perfectly merged arts and science in his life. I have learnt from Stephan a lot, not only in science, but also in many other aspects. Like what Prof. Hideo Ohno said in his email, “he was a great and joyful mentor to us all”. Although Stephan passed away, his spirit is immortal. We will always miss and love him. — Jianhua Zhao, Professor at Institute of Semiconductors, Chinese Academy of Sciences

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I was so saddened to learn of Stephan's passing. He was extraordinarily supportive of me early in my career, and was so free with his time. I owe him a great deal. He was always so genuinely pleased to see me at conferences, meetings, and so on, and that feeling was absolutely mutual. I greatly enjoyed my chats with Stephan, about magnetic semiconductors, oxides, science in general, and everything else. He will be sorely missed by many, well beyond his FSU family.
 — Chris Leighton, University of Minnesota 
	

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I was fortunate enough to work with Stephan after he offered me a post-doctoral position at IBM Yorktown Heights back in 1989 , to investigate diluted magnetic semiconductors. He was always a very supportive and inspiring supervisor, ready to offer praise or scorn if the situation required it. In fact, Stephan passed on to me his enthusiasm for bound magnetic polarons and these magnetic excitations are something that I’m still interested in 30 years later. When I returned to the UK, Stephan still offered support and encouragement and it was always a pleasure to meet up with him when I could. He kindly hosted my visit to MARTECH about 20 years ago, during a period of research leave. Stephan was a very generous man and a great scientist and it has been an honor to have known him.
 — Ian Terry, University of Durham 
	

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Photo of Steve and Jacques Flouquet on the Mediterranean Sea in Palavas
Steve and Jacques Flouquet on the Mediterranean Sea in Palavas
For me, Steve was far more than a creative scientific colleague. His views on different facets of life were always original and often quite different than common wisdom. I have known Steve since 1980. At that time, he was an efficient IBM manager and I was a foreign visitor there for a few months. To avoid responding to difficult questions he would use the following witty trick , saying with a beautiful smile : «Excuse me but I must go to the toilets». Rapidly I realised that I needed to resort to positive remarks. The IBM laboratory in Yorktown Heights was a great place with a lot of freedom [even with problems on fundamental topics that appeared far remote from IBM’s business targets . We were very lucky to host Steve in Grenoble as a guest Professeur. Free from manager duties , I realized how he was an efficient worker with a very easy contact with students . With him we looked at metal insulator transition and at gap emergence in heavy fermion systems like SmB6. I taught him a little bit. For instance that wine must not go immediately in the refrigerator and that there is some relationship between price and quality. I also recognized his innate capacity to interact with very different types of people in the laboratory but also in the broader world. For instance with the owner of his Grenoble flat as well as with the neighbor of his rented flat in Palavas who wanted to break the glass of his rented car after he had left the keys inside. He had his unique way to enjoy seminars, bars, cabarets, theaters and even fist fights between heavy box fighters. Steve had many friends in the scientific community , he paid a key role in opening the door for us of Zachary Fisk mine. Thanks to him we started to work on UBe13 ;with Fred Holtzberg he helped me to be introduced in american meeting. I saw him in Grenoble (when he was invited to give a talk at a spintronic conference ) when I got the news that I had cancer . His positive attitude on life difficulties boosted my moral. Going to Tallahassee for a meeting I was happy to meet Steve with his wife Jean. The sunny days , the less conventional atmosphere of university than IBM were an excellent choice for them. I often asked him about US politics. Generally, he responded within a few days. My last message was a few weeks ago on the US Presidential election. I was surprised that the answer took longer than usual. I then got the news of his death with a deep memory of the lucky and very nice days we spent together. It is now too late for me to ask him the many questions I wished I could ask him. How could he have such a nice and strong character despite the difficulties he had to overcome in his life, notably at his begining during the second war? Meeting his two sons Chris and Marc is one of my priorities. They would help me understand how the unique personality of Steve arose. — Jacques and Francoise Flouquet

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I had the privilege of getting to know Stephan von Molnar while he was my PhD Advisor and Mentor at Florida State University. He was an ideal advisor; he was always there if I needed help or suggestions, but would stand by and let me try things and test out theories on my own. I very much enjoyed his style of mentoring, and learning from such an  influential person in his field. I was so excited when he first accepted me into his group in MARTECH, and I always enjoyed any time spent in his company. 

Steve was always great to talk to about physics. But more than his mentoring, he was a very interesting person and was always fun to chat with about anything. I loved conversing with him about traveling and the places that he had been. I have very fond memories of our group parties, when we would socialize outside of the office. Since we had a large difference in age, I loved talking with him about how he conducted research many years ago, and how it compared to our current research methodologies. Steve was very supportive after I graduated and went on to a postdoc, and then into industry.

Lastly, Steve would always try to make me a better person. He would correct my grammar on a regular basis (I could never get the hang of "Chris and I" instead of "me and Chris").  I would roll my eyes at the time, but even then, I knew he was teaching me something of value. In fact, I learned a whole lot from him academically, personally, and socially. I am sad to hear of his passing. He will be remembered fondly and greatly missed.
 — Jennifer Misuraca 
	

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Photo of Stephan and Peng Xiong conversing at Ted's, circa 2018
Photo of Stephan and Peng Xiong conversing at Ted's
circa 2018
It has been almost two months, it still doesn’t feel real. At any moment, I expect him to walk in, break into that broad smile, and exclaim: “I have another idea!”; or I will hear that booming voice from two doors down: “Peng, I just thought of something!”. There is so much I miss of him: The perpetual optimism, the unparalleled generosity, that delightful and uplifting sense of humor, and most of all, the tenacious passion for ‘good physics’. For more than twenty years, Stephan and I shared much common interest in physics, many labs and equipment, a number of joint grants, and quite a few graduate students and postdocs. I was fortunate enough to be able to not only talk to him on daily basis, but also share many long drives and flights, from which I learned about his extraordinary childhood in war-time German countryside, his carefree teenager years in NYC, his cross-country hitchhike to Nevada, his conflict between the callings of theater versus physics, his admiration and disdain of famous and infamous physicists. I could always count on him for insight in physics, wisdom on life, perspectives of history and politics, and above all, honest assessment and frank critiques of my work. Stephan’s enormous generosity occasionally masked his fierce competitiveness; I found that out firsthand when he invited me for a squash game when he was 77. A brilliant scientist and true gentlemen; a gentle giant indeed. Cheers, my friend! — Peng Xiong, professor of physics, Florida State University

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Photo of Stephan and Jens Müller in Frankfurt, 2017
Photo of Stephan and Jens Müller in Frankfurt
2017
Stephan was not only my postdoctoral mentor but also a fatherly figure and dear friend – above and beyond scientific matters. His enthusiasm was inspiring and his knowledge immense. I joined MARTECH at FSU as a PostDoc in 2003. “OK, kiddo...” is how Stephan used to end discussions. This meant that for now everything was said, and I knew I needed to do some homework. From that time a close and dear relationship remained not only with Stephan but also with members of his and Peng Xiong’s research groups. Until now, these collaborations and friendships are very dear to me, also because Stephan’s spirit is conserved in them. After I left FSU in 2006 for joining the Max-Planck-Institute for Chemical Physics of Solids (MPI-CPfS) in Dresden and later Goethe-University Frankfurt, Stephan visited several times, he gave talks at the institute and we did boat tours on the river Rhine. Fond memories of him and Jean enjoying the medieval castles and a Whisky on the boat deck remain with me to this day. The picture has been taken at his last visit in Frankfurt in 2017. Late in the summer of 2020, together with Steffen Wirth from the MPI-CPfS in Dresden we had a lively Zoom discussion on magnetic polarons in a Eu-based CMR material. Stephan was sharp-minded as ever, full of references to former work and enjoyed being snarky, in a nice way, when discussing data of the literature. At that time, we didn’t think that this would be our last discussion on physics. Later, we kept exchanging emails, and Stephan explained his point of view of this “terribly complicated material” in his usual Stephan sharpness. He is dearly missed. — Jens Müller, professor of physics, Goethe University Frankfurt

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Photo with Xiong group members in front of Keen building in Oct 2016
Alongside Xiong group members in front of Keen building
Oct 2016
Photo from Steve's former student Jelena Trbovic visiting in Sept 2019
At Harry's Seafood, when Steve's former student Jelena Trbovic visited Tallahassee
Sept 2019
Photo where Stephan gave a talk at IoS, Beijing in 2008
Stephan gave a talk at IoS, Beijing
2008
Photo where Stephan chaired a joint workshop Beijing in 2011
Stephan chaired a joint workshop Beijing
2011
Photo where Stephan gave a talk at IoS, Beijing in 2008
Stephan gave a talk at IoS, Beijing
2008
Photo of Stephan in Beijing, 2011
Stephan was in Beijing
2011
Photo where Stephan and his wife Jean were in Beijing, 2008
Stephan and his wife Jean were in Beijing
2008
Photo where Jianhua was with Stephan, Peng and their students, taken at Tallahassee, 2010
Jianhua was with Stephan, Peng and their students, taken at Tallahassee
2010
Photo of Steve and Peng research group
Steve and Peng research group