In the last weeks, I had two seminar talks: one from Uni-Halle in Germany and the other from CNRS-Thales in France. Due to current situation with COVID, both seminars were held online. The title of my seminar was "Orbital transport in spintronics" (yeah, that's so surprising 😀). While the contents were almost identical, I prepraed …
Finally accepted: Orbital torque in AlOx/Cu/FM
The manuscript "Non-trivial charge-to-spin conversion in ferromagnetic metal/Cu/Al2O3 by orbital transport" was finally accepted from Physical Review B Rapid Communications (now it's called Letter). It was not really easy to get this manuscript published, which took more than 2 years. It was beginning of 2018 when I heard that SOT in AlOx/Cu/FM is surprisingly large. …
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Orbital Rashba effect in surface oxidized Cu (a new preprint is out!)
Recently, I wrote an article about the experiment from Kläui-Lab on surface-oxidized Cu. Since we publisehd this work, I decided to "find" the orbital Rashba effect in this material system. Implications from several experiments were quite clear: There must be something with orbital. So, it was actually more a matter of "how" I find the …
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Updating codes for colleagues (and also for my future works)
Over the last week, a new postdoc and students arrived in our group. So, I decided to give an informal tutorial for them. I just opened a zoom meeting room, shared my screen with black terminal windows, and showed them, for example, how to reproduce key data figures of theory papers. In my opinion, the …
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Conferences
In this week, I participated in two different conferences, both of which were held online. The first conference that I joined was Young Research Leaders Group Workshop organized by Alexander Mook and Helena Reichlova through SPICE in JGU Mainz. The idea was to bring junior researchers over the world in one place to share ideas …
Surface-oxidized Cu can generate orbital current
Controversy over the surface-oxidized Cu goes back to 2016, where An et al. from Keio University published a paper that demonstrates significantly large spin-orbit torque as Cu/Py/substrate structure becomes "naturally" oxidizied from the Cu surface. This seems like a typical setup to characterize self-induced spin-orbit torque in Py assuming that Cu doesn't induce any significant …
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Transition metal dichalcogenides are orbital Chern insulators
An interesting feature of the topological insulators is that even though the bulk is insulating it is guaranteed that there is a metallic boundary state, which is called a topological surface/edge state. There are various topological phases depending on symmetries that protect the topological invariant of the system. For example, for quantum spin Hall effect, …
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Relaxing weekend
During the weekend, I stopped thinking about the orbital current and enjoyed nature around my home since my friends came to visit me. I was quite surprised to see that so many trees are already in colors. Sometimes when I foucs on the work, the life becomes like a series of office-home-office-home- ... that repeats …
Making orbital current meter
In Inventing Temperature by H. Chang, the author asks a simple question: How did people made the thermometer and measured the temperature for the first time? If you are to make a thermometer, you need to know the temperature. But to know the temperature, you need a thermometer. It seems like an infinite logical loop …
Writing an introductory article in Korean
Since last Friday, I have been writing an introductory article about my research area: orbital current and its electrical generation. While most of scientific articles are written in English nowadays, this time I am writing in my mother tongue, Korean. It is to be publised in "Physics and Modern Technology", a magazine issued by Korean …
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Spintronics, Orbitronics, and Physics Beyond 