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Posted in 2010

Summary 2010

Let me summarize the year: assuming nothing drastic would happen in several hours left.

It was a year full of motion and new impressions. I travelled a lot: I’ve been three times in Germany, twice in US and Russia, I got to Japan, Sweden, France, and even Belgium. I’ve met many old friends, and got new collaborators: Frans Godschalk, Dima Pikulin, Toshi Kubo. 6 papers have appeared in press. I’ve got several good scientific ideas, two of them promise a long interesting research, potentially opening new fields. I gave a lecture at my alma mater and survived Colorado highlands. From community side, Leo DiCarlo, Gary Steele, Sander Otte have joined our faculty. Andre Geim got Nobel prize. On family frontline, my eldest son Alexei graduated and has departed overseas in pursuit of Ph. D.

That was good. There were many things happening that were not really bad but were wounding my vanity. There were many things I intented to work on or accomplish but have done nothing about. My favourite research lines slowly drop out of fashion. I’ve been cited 551 times, 8% less than a year ago. None of my grant applications has been approved. There was a discussion to propose me for a big local prize: nothing came about. The list of articles that are finished but wait for write-up has not become shorter: it’s grown. I am especially unhappy about non-written research with Hongduo Wei. Nothing has been done with my personal website. Alex Savchenko and Mike Tinkham have departed from this world. On family front, the youngest son has been having all kinds of problems with his studies.

Give me, my Lord, the mood to thank you for everything from the two above lists. And perhaps, if you find it useful, the ability to learn the lessons you give to me.

Coulomb Blockade due to Quantum Phase-Slips Illustrated with Devices

is a long title of a long article we have submitted to arXive today. Alina Hriscu has been working the whole year on the topic, even today in the morining. I am happy we manage to submit it yet this year.

In this article, in order to illustrate the emergence of Coulomb blockade from coherent quantum phase-slip processes in thin superconducting wires, we propose and theoretically investigate two elementary setups, or “devices”. I will post the reference to cond-mat soon.

Stevan Nadj-Perge

born in Kikinda, Serbia, has secured his Ph.D. title yesterday.
The promotor was Leo Kouwenhoven. The back side of the thesis showed a quantum yo-yo, an indespensible component of quantum calculations. The title of the thesis was “Single Spins in Semiconductor Nanowires”

During the event, the “dark years” have been mentioned many times: 2,5 years Stevan has spent in clean room trying to fabricate, for no avail. The sucsess has come relatively recently, and the thesis contains several important achivements, including of course the “Disentangling”, the topic we have collaborated on.

Good luck, Stevan, with futher carrier. Many remember your perfect smile that persisted even during “dark years”. I was impressed with your propositions: they were so correctly unpractical or, to formulate it better, so unpractically correct. I could sign every of them, provided I’m a bit yonger and can afford being unpractical.

St. Nicholas day

is today (according to our Church calendar).

St. Nicholas is patron saint of Amsterdam and Russia, so naturally our parish is the St. Nicholas parish. There must be a big feast over there today. We wished to attend this, but we cannot: 10 cm snow has fallen tonight, and public transportation does not like this. A bit dissapointed, we celebrate at home.

This is the name day of my handicapped son, who will turn seventeen soon. This is also the name day of an old Russian surgeon who has saved life of my wife about thirty years ago.

Holy father Nicholas, defender and wonderworker, recall them and all us seeking your help in your prayers.

Matti Laakso

my Finnish collaborator, was visiting Delft in the week past. Unfortunately, it was rather busy and chaotic week and I cannot work with him as much as I wanted. Still, we were able to achieve some serious progress regarging the processes that determine overheating in superconductor-insulator-normal metal-insulator-superconductor structures (SINIS, it only sounds that long and artificial, it fact, this is a very natural structure and is relatively easy to make).

Matti is going to complete his PhD thesis in coming year.

On his way back, he had a mixture of trouble and luck. There was again a snowfall on Friday, and again the transport managers have been caught unguarded (what is going on with this country anyway…) Three thousand people have been stranded at Schiphol airport, and estimated three thousand could not reach it at all. On this background, Matti was relatively fortunate. He’s only spent an hour in a train that has stuck in Schiphol tunnel, waited three extra hours for his flight (the only one within Europe that has not been cancelled) and managed to get home on the same night.

So I wish him best luck with his PhD thesis as well.

Roma, citta di eterno amore

I’ve promised a nice trip to my mother on occasion of her birthday. That should have happen in April, but the volcano has cancelled our trip. So this was a second attempt.

In the beginning, it was not better than the first one. We were to depart on Saturday Dec. 4, and there was a catastrophy: a snowfall. Notwithstanding the fact that such phenomena occur in this country with strange regularity, nobody seemed to be expecting this. The public transportation was paralyzed. Our train trip to Schiphol took three hours. It could take five, but we took a taxi cab from Amsterdam Zuid. With a great moral and financial effort, we have arrived on time for our flight. Our happiness did not last long: the flight has been cancelled, nobody could overbook it and nobody could even free our laggage trapped in Schiphol catacombs. To make a long story short, we have arrived to the Eternal city only on Sunday 23:55, to learn that there are no regular ways to leave the airport that late…

Anyway, we had Monday, Tuesday and most of Wednesday to enjoy Roma. It was warm and reasonably dry. Since my mother was there for the first time, we did all usual touristic things like jumping over stones of Forum, queuing to St. Peter’s cathedral, rushing through Borghese gallery. Less touristic things included the visit to Sancta Sanctorum where I contributed to polishing of Scala Santa with my knees, and unplanned encounter with the Pope on piazza Spagna on occasion of the feast of Immaculate Conception (being Orthodox, we were not even aware of the feast).

The way back was not trivial either. It looks like if one takes a taxi in the beginning of the trip, one keeps taking it till the end, and missed trains and trams just provide a good excuse to enjoy this kind of transportation.

Visit NEC Tsukuba

I reserved a day, my last day in Japan, to visit NEC Tsukuba, were Jaw-Shen Tsai, Yasunobu Nakamura, Yuri Pashkin and Oleg Astafiev do almost unbelivable things about quantum manipulation. Their (pioneering) works with qubits are well-known, now in addition to it they do nanomechanics, non-linear quantum optics with microwaves and always eager to talk about new things, like phase-slips etc.

I was trying to promote the phase-slips in my talk but they’ve already did some preliminary experiments and were dissappointed. Perhaps Oleg will be able to combat this feeling. Anyway, there were more than many discussion topics, and I’ve spent the whole day talking

We’ve rounded the day with a nice party: thanks so much, my hosts.

Good time at NTT

It is more than a week I am back from NTT. It was a very good visit, both productive and informative. Here are some highlights.

With Yasuhiro Tokura, we have started collaboration on nuclear punping effects on transport in quantum dots. With Toshihiro Kubo, we have started collaboration on mesoscopic interference effects in two quantum dots. I hope very much we can bring these challenging and interesting projects to the end.

Makoto Yamashita has explained me his research in cold atoms, in particular, his studies of Bose shells. Tetsuya Mukai has shared his ideas of atom chip where several atoms are trapped above the surface of a superconductor with magnetic field of superconducting currents.

I listened to the talk of Fumiki Yoshihara from NEC Tsukuba: he presented a long-awaited experimental charactetization of flux noise in superconducting qubits. The noise seems to come from the surface. Hayato Nakano gave a detailed review of his work on “practical” measurement, theoretical research on details of collective quantum mechanics of a qubit and a detector.

Hiroshi Yamaguchi has open me new horizons in nanomechanics: he has original thoughts and plans that differ from those I accustom to. How about a computer solely based on non-linearities of nanomechanical resonators?

Many if not most discussions have been with Koji Muraki, the head of quantum dot group, his students and postdocs. I have learned about the gap at nu=2/5, was updated on charge qubits, charge measurement, exotic Kondo and, of course, on nuclear pumping effects. Here, I guess, Tokura and me were able to contribute to understanding of the experiment

Michael Tinkham

is not with us anymore. This has happened two weeks ago, but I’ve learned about it only today. He was 82, and our last scientific communication was less than four years ago.

Michael Tinkham was not just a classic writer and pioneer of the superconductivity: for me, it was like the superconductivity itself. His ability to comphrehend the things about it, and his taste for novelty and unusual аspects of physical phenomena were almost beyond imagination. In his advanced ages, he looked nothing like a monument to his own merits: rather, he acted as a person in very beginning of his scientific carrier, looking for news and being eager to learn.

Our last communication was about quantum phase slips: he wanted to achieve an unambiguous experimental proof of their existence.

Grant rest, o Lord, to the soul of Thy servant Michael.

Nuclear spin pumping and electron spin susceptibilities

was a topic of our deep considerations with Jeroen Danon. These considerations have started when Jeroen was a second-year ph.d. student, and now, as Jeroen is already more than a year in Berlin, finally converged to a form of a paper submitted. You can find it here.

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