Wednesday, May 22, 2013

Deceased--Heinrich Rohrer

Heinrich Rohrer
June 6th, 933 to May 16th, 2013

"Heinrich Rohrer, Nobel Prize-winning physicist, dies at 79"


Martin Weil

May 21st, 2013

The Washington Post

Heinrich Rohrer, a Swiss physicist and one of the two Nobel Prize-winning scientists who helped make possible the modern field of nanotechnology by inventing a microscope that could readily see individual atoms, died May 16. He was 79.

The Swiss newspaper Tages-Anzeiger reported that he died at his home in Wollerau, Switzerland. The cause of death was not disclosed.

The device Dr. Rohrer created at an IBM laboratory in 1981 with Gerd Binnig was called the scanning tunneling microscope, and they shared half of the physics Nobel in 1986. (German scientist Ernst Ruska also received a physics prize that year for unrelated work on the electron microscope.)

The device became a pillar of nanotechnology, the ma­nipu­la­tion of individual atoms and molecules to create useful devices. Nanotechnology deals with dimensions on the order of a few millionths of an inch. Objects that size cannot be seen with the most powerful optical microscope.

But quantum mechanics, the theory of matter on the atomic scale, helped point a way forward for Dr. Rohrer and his colleagues. In quantum theory, electrons have wavelengths, which are smaller than those of visible light. Thus, microscopes using electron beams rather than beams of light can see smaller objects.

The devices stemming from Dr. Rohrer’s work are even more powerful than the basic electron microscope. In part, they depend on a particularly startling feature of quantum reality: quantum tunneling.

In the quantum world, electrons can be in two places at once; they can show up on both sides of a seemingly impenetrable barrier. This phenomenon comes about through what is known as quantum tunneling, and the scanning tunneling microscope depends on it.

In the device, a probe with a tip as fine as a single atom moves over the surface of a material. Electrons tunnel through the minuscule gap between probe and surface. The current produced in this way varies with the distance between the probe and the surface.

High points on a surface, closer to the probe, create stronger current. For low points, the current is weaker. Charting the current yields a map of the surface.

Dr. Rohrer and his co-inventor produced an image suggesting a landscape of hills and valleys. But, they wrote, they recognized this image for what it was. They knew that the “pronounced and regularly arranged protrusions we saw” were actually individual atoms.

They had been told that such a precise finding was impossible.

“Rumors reached us that scientists would bet cases of champagne that our results were mere computer simulations!”
they wrote. But their success soon became clear.

Heinrich Rohrer was born June 6, 1933, in Buchs, Switzerland, and moved with his family to Zurich as a teenager. Acknowledging that he was not one who had dreamed since childhood of physics, he nevertheless took it up at the Swiss Federal Institute of Technology in Zurich and went on to obtain bachelor’s and doctoral degrees there in 1955 and 1960, respectively.

After two years of postdoctoral work at Rutgers University in New Jersey, he returned to Switzerland in 1963 to work for IBM, where he conducted his prize-winning scientific investigations. Binnig worked for Dr. Rohrer at his laboratory in Zurich.

Survivors include his wife since 1961, Rose-Marie Egger, and two daughters.

At the outset of their Nobel lecture, Dr. Rohrer and Binnig said it was intended as a report on how they had worked, not as a recommendation for how others should work. In addition, they said, “it would certainly be gratifying if it encouraged a more relaxed attitude towards doing science.”


I was born in Buchs, St. Gallen, Switzerland on 6.6., '33 as the third child, half an hour after my twin sister. We were fortunate to enjoy a carefree childhood with a sound mixture of freedom, school and farm work. In 1949, the family moved to Zürich and our way of life changed from country to town. My finding to physics was rather accidental. My natural bent was towards classical languages and natural sciences, and only when I had to register at the ETH (Swiss Federal Institute of Technology) in autumn 1951, did I decide in favor of physics. In the next four years, Professors G. Busch, W. Pauli, and P. Scherrer taught me the rudiments. In autumn 1955, I started work on my Ph.D. Thesis and it was fortuitous that Jörgen Lykke Olsen trusted me to measure the length changes of superconductors at the magnetic-field-induced superconducting transition. He had already pioneered the field with measurements on the discontinuity of Young's modulus. Following in his footsteps, I lost all respect for angstroms. The mechanical transducers were very vibration sensitive, and I learned to work after midnight, when the town was asleep. My four graduate years were a most memorable time, in a group of distinguished graduate students always receptive for fun, and including the interruptions by my basic training courses in the Swiss mountain infantry.

In summer 1961, Rose-Marie Egger became my wife, and her stabilizing influence has kept me on an even keel ever since. Our honeymoon trip led us to the United States where I spent two post-doe years working on thermal conductivity of type-II superconductors and metals in the group of Professor Bernie Serin at Rutgers University in New Jersey. Then in the summer of 1963, Professor Ambros Speiser, Director of the newly founded IBM Research Laboratory in Rüschlikon, Switzerland, made me an offer to join the physics effort there. Encouraged by Bruno Lüthi, who later became a Professor at the University of Frankfurt, and, at the time, strongly recommended the hiring of Gerd Binnig, I accepted to start in December 1963, after having responded to the call of the wild in the form of a four-month camping trip through the USA.

My first couple of years in Rüschlikon were spent studying mainly Kondo systems with magnetoresistance in pulsed magnetic fields. End of the sixties, Keith Blazey interested me to work on GdAlO3, an antiferromagnet on which he had done optic experiments. This started a fruitful cooperation on magnetic phase diagrams, which eventually brought me into the field of critical phenomena. Encouraged by K. Alex Müller, who had pioneered the critical-phenomena effort in our Laboratory, I focused on the bicritical and tetracritical behavior and finally on the random-field problem. These were most enjoyable years, during which so many patient colleagues taught me physics. I left them with some regret, when I ventured with Gerd to discover new shores. We found them. Thank you, Gerd.

In 1974/75, I spent a sabbatical year with Professor Vince Jaccarino and Dr. Alan King at the University of California in Santa Barbara, to get a taste of nuclear magnetic resonance. We solved a specific problem on the bicritical point of MnF2, their home-base material. We traded experience, NMR and critical phenomena. Rose-Marie and I also took the opportunity at the beginning and end of my sabbatical to show the USA to our two daughters, Doris and Ellen, on two extended camping trips from coast to coast.

In all the years with IBM Research, I have especially appreciated the freedom to pursue the activities I found interesting, and greatly enjoyed the stimulus, collegial cooperation, frankness, and intellectual generosity of two scientific communities, namely, in superconductivity and critical phenomena. I should also like to take this opportunity to thank the many, many friends, teachers, and seniors who have contributed towards my scientific career in any way whatsoever, and most particularly my mother for her unstinting aid and assistance, especially when times were difficult.

Heinrich Rohrer [Wikipedia]

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