Your source for the latest science & space news

Saturday, 16 November 2019

Discovery of a new state of matter: metallic Cooper pairs


Described for the first time in 1956, the Cooper pairs are low temperature electron bound states responsible for the superconductivity phenomenon. In today's quantum models, these pairs can be either zero electrical resistance or electrical insulation. However, physicists have discovered a new state of matter in which Cooper pairs conduct electricity while generating some resistance, just like ordinary metal. A phenomenon not foreseen by the physics of condensed matter and which could lead to the development of new electronic devices.



For years, physicists have assumed that the Cooper pairs, the electron pairs that allow superconductors to drive electricity without resistance, were binary systems. The pairs slide freely, creating a superconducting state, or an insulating state by getting stuck in a material, unable to move.


Pairs of Cooper: they can combine conductivity and electrical resistance

But in a new article published in the journal Science , a team of researchers has shown that Cooper's pairs can also conduct electricity with some resistance, as do ordinary metals. The results describe a new state of matter, according to the researchers, which will require a new theoretical explanation.

" It had been proven that this metallic state would form in thin-film superconductors as they cooled down to their superconducting temperature, but the question of whether this state involved Cooper pairs is an open question, " says Jim. Valles, professor of physics at Brown University.

" We have developed a technique that allows us to answer this question and we have shown that, as a result, Cooper pairs are responsible for carrying the charge in this metallic state. What's interesting is that no one is really sure how it works. This discovery will therefore require more theoretical and experimental work to understand exactly what is happening."

Cooper pairs and superconductivity

Cooper's pairs are named after Leon Cooper, professor of physics at Brown, who won the Nobel Prize in 1972 for describing their role in superconductivity. Resistance is created when electrons vibrate in the atomic network of a material as they move. But when the electrons unite to become Cooper pairs, they undergo a remarkable transformation.

The BCS theory explains the phenomenon of superconductivity by the appearance of Cooper pairs. At very low temperatures, the electrons pair together (b), forming many Cooper pairs within the material (c). These pairs occupy the same fundamental quantum state and form a single quantum wave (d). Cooper pairs are treated as bosons, they obey Bose-Einstein statistics and are not subject to the Pauli exclusion principle. Credits: CNRS


The electrons themselves are fermion s, particles that obey the Pauli exclusion principle, which means that each electron tends to maintain its own quantum state. The Cooper pairs, however, act as bosons, which can share with the same state. This bosonic behavior allows Cooper pairs to coordinate their movements with other sets of Cooper pairs, so as to reduce electrical resistance to zero.


A new bosonic state of Cooper pairs

In 2007, Valles, in collaboration with Jimmy Xu, Professor of Engineering and Physics at Brown, showed that Cooper's pairs could also produce insulating states as well as superconductivity. In very thin materials, rather than moving together, couples stay in place, grouped by islands without means to join those around.

Scanning electron microscope observation of the material used for the experiment: a YBCO superconductor with a network of tiny holes to study the dynamics of the Cooper pairs. Credits: Brown University

For this new study, Valles, Xu and his colleagues searched for non-superconducting metallic Cooper pairs using a technique similar to that which revealed insulators of Cooper pairs. This technique consists of modeling a thin-film superconductor, in this case a high-temperature superconducting yttrium, barium and copper oxide (YBCO), with networks of tiny holes.

When the material is traversed by a current and is exposed to a magnetic field, the charge carriers of the material gravitate around the holes like water surrounding a drain. " We can measure the frequency with which these charges revolve around. In this case, we found that the frequency is compatible with the fact that two electrons circulate at once instead of one. So we can conclude that the charge carriers in this state are Cooper pairs and not electrons, "says Valles.


Towards the potential development of new electronics

The fact that this phenomenon has been detected in a high temperature superconductor will make future research more practical. The YBCO type begins its superconductivity at about -181 ° C and the metal phase begins at a temperature just above that. This higher temperature facilitates the use of spectroscopy and other techniques to better understand what is happening in this metallic phase.

According to the researchers, it may be possible to exploit this bosonic metal state for new types of electronic devices. " The problem with bosons is that they tend to be in a wave state more like electrons. We are talking about a phase and interference similar to that of light. So there may be new ways to move the load in the devices by playing with interference between the bosons "concludes Valles.

Bibliography:

Intermediate bosonic metallic state in the superconductor-insulator transition

Science 14 Nov 2019:
eaax5798
DOI: 10.1126/science.aax5798 

Source

32 comments:

  1. You have done a great job. I will definitely dig it and personally recommend to my friends. I am confident they will be benefited from this site.galaxy poker

    ReplyDelete
  2. Are we getting fake survival warnings to prepare ourselves when there is still time? Fake news is not a recent phenomenon and has existed for a long time but its impact has become more widespread with the spread of the internet and social media. Fake news can be described as a completely fabricated story without any basis that has been floated by vested interests to serve their own purpose. jiu jitsu beginners

    ReplyDelete
  3. Fantastic blog! I dont think Ive seen all the angles of this subject the way youve pointed them out. Youre a true star, a rock star man. Youve got so much to say and have a lot of knowledge about the subject that I think you should just teach a class about it…HaHa! unlock iphone

    ReplyDelete
  4. Super site! I am Loving it!! Will return once more. I'm taking your sustenance in addition. 우리카지노

    ReplyDelete
  5. With the advance of technology and digital media, world news can be viewed online instead of the age old newspaper. Newspapers find it hard to keep up with the trend of online news which can be viewed over the internet. china news

    ReplyDelete
  6. I really appreciate this wonderful post that you have provided for us. I assure this would be beneficial for most of the people. 우리카지노

    ReplyDelete
  7. Thank you so much for sharing this amazing article with us.Will stay connected with your blogs for the future posts Nrtec

    ReplyDelete
  8. I am crazy about this blog. I have visit so many time to this blog. I was found this blog from Google. I have received a nice stuff of information. I really appreciate to meet to it and i emphasize to this blog. My curiosity to learn more and more on this blog Narasaraopeta Engineering College

    ReplyDelete
  9. there are many different operating systems but of course i would still prefer to use linux for stability,. One Shot Keto Reviews - AP News

    ReplyDelete
  10. What an interesting story! I'm glad I finally found what I was looking for 바둑이사이트.

    ReplyDelete
  11. I am contemplating this topic. I think you can solve my problems. My site is at "카지노사이트". I hope you can help me.

    ReplyDelete
  12. Recently, I have started to read a lot of unique articles on different sites, and I am enjoying that a lot. Although, I must tell you that I still like the articles here a lot. They are also unique in their own way. 토토사이트

    ReplyDelete
  13. First of all, I would like to thank you for writing this article. I'm trying to make an article by citing your article.먹튀신고

    ReplyDelete
  14. Thank you and thank you so much. I'll share you useful information.토토사이트

    ReplyDelete
  15. Extraordinary blog. I took pleasure in scrutinizing your articles. This is extremely a marvelous scrutinized for me. I have bookmarked it and I am suspecting examining new articles. Continue doing magnificent! Harry potter wand

    ReplyDelete
  16. I am always searching online for storys that can accommodate me. There is obviously a multiple to understand about this. I feel you made few salubrious points in Attributes moreover. Linzhi Phoenix

    ReplyDelete
  17. With the advance of technology and digital media, world news can be viewed online instead of the age old newspaper. Newspapers find it hard to keep up with the trend of online news which can be viewed over the internet. Incredible Mag

    ReplyDelete
  18. With the advance of technology and digital media, world news can be viewed online instead of the age old newspaper. Newspapers find it hard to keep up with the trend of online news which can be viewed over the internet. Soi 6

    ReplyDelete



  19. 라이센스 : 필리핀 정식 합법 라이센스 게임영상 : 부웅고게임/판타즈마/어거스트게이밍/게임아트/플레이스타/푸쉬게이밍/블루프린트 등 27개 게임사 제공 신규 가입혜택 : 가입 머니 2만원(입금액과 같이 사용 가능) 입금 보너스 : 매일 첫입금 20% (MAX 무제한)/매일 재입금 5% (MAX 무제한) 슬롯업계 중 가장많은 보너스혜택 제공 / 모든게임 롤링 100%
    슬롯사이트


    ReplyDelete
  20. Thank you so much for providing good quality information. I think it would not have been easy to collect this information and organize it in an easy to understand way. I'll add it to my bookmarks so I can visit it often! And I will share it with my acquaintances. And there is a lot of useful information on our website too, so please take a look and take a look. Then have a good day. 먹튀검증

    ReplyDelete
  21. This is one very interesting post. I like the way you write and I will bookmark your blog to my favorites. 온라인홀덤

    ReplyDelete
  22. Credit Yatra promises to be a fair and objective portal, where readers can find the best business information, credit cards, bank loans, free credit scores etc.best home loans in india

    ReplyDelete
  23. Narsaraopeta Engineering College (NEC) an Autonomous Institution is yet another shining example of "Dedication for Education". ice=" Top Engineering Colleges in Guntur Quality, which is the hallmark of Gayatri Educational Development Society (GEDS) is the patron and proud sponsor of NEC. In 1998, the portals of NEC were opened for all the scholars across the globe.

    ReplyDelete
  24. Larkya Online shopping site in Andhra and Telangana. Larkya makes the Fashion and Accessories to be in your Hands for Women, Men and Kidswear .
    larkya.in

    ReplyDelete
  25. I don't know how many hours I've been searching for a simple article like this. Thanks to your writing, I am very happy to complete the process now. 안전놀이터

    ReplyDelete
  26. It will always be interesting to read content from
    other writers and practice something from their sites. 출장안마


    ReplyDelete
  27. Larkya Online shopping site in Andhra and Telangana. Larkya makes the Fashion and Accessories to be in your Hands for Women, Men, Kidswear and Leather Bags
    Leather Bags

    ReplyDelete
  28. Thanks for your marvelous posting! I actually enjoyed reading it, you could be
    a great author.I will remember to bookmark your blog and will
    eventually come back from now on. I want to encourage you to continue your great
    writing, have a nice weekend!egaon casino

    ReplyDelete
  29. You're so interesting! I don't suppose I've read anything like this before.
    So great to find someone with a few unique thoughts on this issue. Seriously.. many thanks for starting this up. This site is something that is needed on강남오피


    the internet, someone with some originality!

    ReplyDelete
  30. Hi there, I simply hopped over in your website by way of StumbleUpon. Now not one thing I’d typically learn, but I favored your emotions none the less. Thank you for making something worth reading. 먹튀검증업체

    ReplyDelete