tag:blogger.com,1999:blog-13869903.post5438419279331071425..comments2024-03-27T18:46:34.971-05:00Comments on nanoscale views: A scientific direction that I think is promisingDouglas Natelsonhttp://www.blogger.com/profile/13340091255404229559noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-13869903.post-55100287948333284542007-02-15T08:25:00.000-06:002007-02-15T08:25:00.000-06:00Hi Sujit - Relatively little work of this nature ...Hi Sujit - Relatively little work of this nature has been done, or at least published. The recent paper on field-effect modulation of Tc in a few-unit-cell-thick high-Tc layer is the best example that comes to mind. In my own group we've got some tantalizing unpublished results in one nanomaterial, but it's early days yet.<BR/><BR/>Regarding John Wei's nice work at Toronto: I don't think it really qualifies, in that the actual superconducting strips, while 50 nm <I>thick</I>, are 1 millimeter wide. That doesn't really fit my description, though it does raise the issue of what is the effective dimensionality for strongly correlated systems. If the correlation physics (e.g. strong on-site repulsions on copper ions, as in the copper oxide superconductors) is very local, does that mean that a few unit cells is enough to get essentially bulk material?<BR/><BR/>Raj's work is actually a good example of the fab challenges. I'm assuming there's a good reason why they haven't published anything else from those structures in the last three years.Douglas Natelsonhttps://www.blogger.com/profile/13340091255404229559noreply@blogger.comtag:blogger.com,1999:blog-13869903.post-30425980152541873512007-02-13T21:05:00.000-06:002007-02-13T21:05:00.000-06:00I don't know if anyone else is doing work of a sim...I don't know if anyone else is doing work of a similar nature, but the website for the UofT group I mentioned is <A HREF="http://www.physics.utoronto.ca/~wei/" REL="nofollow">here</A>. The paper I was talking about is <A HREF="http://www.physics.utoronto.ca/%7Ewei/Suppression_Andreev_Supercurrent_YBCO_PRB_2005.pdf" REL="nofollow">this one</A>. There's a Proceedings of SPIE paper that summarizes some of the stuff available <A HREF="http://www.physics.utoronto.ca/%7Ewei/SPIE_2005_preprint.pdf" REL="nofollow">here</A>. <BR/><BR/>Basically, they have done STS on YBCO thin-film strips and transport measurements on doped YBCO 'microwires'. What are your thoughts on this?<BR/><BR/>(Also, I came across another paper - "Nanoscale high-temperature superconductivity" - coauthored by them and Mohanty at BU, that mentions this work - available <A HREF="nano.bu.edu/nano-hts.pdf" REL="nofollow">here</A>.)Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-13869903.post-54635493912309597422007-02-13T20:54:00.000-06:002007-02-13T20:54:00.000-06:00Are there any references you can provide on work o...Are there any references you can provide on work of this nature that may have already been done? You mention fabrication challenges - do you know of any work on this? <BR/><BR/>Is studying nanoscale-width strips of thin films relevant to what you are talking about? For example, I think I remember coming across work by a group at the University of Toronto who did STS on YBCO thin film strips of width ~50nm. I can't remember the reference off the top of my head but will try to dig it up.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-13869903.post-79285538668849276192007-02-11T07:58:00.000-06:002007-02-11T07:58:00.000-06:00Gee and I was expecting a blog entry about the lat...Gee and I was expecting a blog entry about the latest news out of Princeton concerning the ESP lab there...Anonymousnoreply@blogger.com