|CV and list of
- PHD STUDENT POSITIONs
- POSTDOCTORAL POSITION
- SEVERAL POSSIBLE PROJECTS FOR MASTER STUDENTS
Applications are accepted by email
Fellow of the Royal Swedish Academy of Sciences
(KVA Forskare) hosted at KTH Stockholm
and Ass. Prof. University of Massachusetts Amherst
emails (these email addresses do not work
reliably, so you can send messages to
both if I do not answer):
babaev "at" kth "dot" se
egorbabaev "at" gmail "dot" com
PhD Uppsala University, Sweden ->
Research Associate Cornell
-> Ass. Professor University of Massachusetts Amherst
Royal Swedish Academy Fellow hosted at KTH Stockholm
- Tage Erlander prize from the Swedish Royal Academy of Sciences
citation: "for groundbreaking theoretical work that predicts
new states of matter in the form of quantum fluids with novel properties"
- US National Science Foundation CAREER award.
NSF award description: "CAREER Program is a Foundation-wide activity that offers the
US National Science Foundation's most prestigious awards in support of junior faculty"
- Knut and Alice Wallenberg award, fellow of the Swedish Royal Academy of Sciences
Swedish Royal Academy award description: "Awards are given to exceptionally
gifted researches to carry out their research in Sweden".
- University of Massachusetts Exceptional Merit Award
- American Physical Society Oustanding Referee Award.
Johan Carlstrom (KTH)
Karl Sellin (KTH)
Daniel Weston (KTH)
Qingyou Meng (UMass)
Julien Garaud (UMass)
Past group member
Mihail Silaev (Postdoc 50%
split appointment with
IPM Russian Academy of sciences),
returned to permanent
positionm at IPM RAS
Assistant Professor University of
New popular article on our research:
Physicists unveil a theory for a new kind of superconductivity
I was organizing "Fontiers in Condnesed Matter Physics conference" January 2011
as well as
The international on Quantum solids liquids and gases which we organized in Stockholm this summer is over, the talks are uploaded online
Talks of the past Quantum Fluids 2007 workshop are also available online http://www.nordita.org/~qf2007
Tage Erlander prize in physics awarded by the Royal Swedish Academy of Science
"for groundbreaking theoretical work that predicts new states of matter in the form of quantum fluids with novel properties"
Foto: Markus Marcetic copyright The Royal Swedish Academy of Sciences
A conventional superconductor is described by two fundamental length scales, the magnetic field penetration depth and the coherence length. Their ratio determines the response of a superconductor to an external magnetic field, sorting them into two categories as follows; type-I when it is small and type-II whent it is large In http://arxiv.org/abs/cond-mat/041168 http://arxiv.org/abs/cond-mat/0302218 we discussed that in multicomponent systems this dichotomy can be broken and that there could be a different regime (recently termed "type-1.5" superconductivity) where there could be two coherence lengths, some smaller and some larger than the penetration length a consequence of the extra fundamental length scale, vortices attract one another at long range but repel at shorter ranges. As a consequence the system should form an additional Semi-Meissner state. In that state vortices form clusters in low magnetic fields. Inside the cluster one of the component is depleted and the superconductor-to-normal interface has negative energy. In contrast the current in second component is mostly concentrated on the cluster's boundary, making the energy of this interface positive
See also a news story in Science Magazine "New Type of Superconductivity Spotted" and a feature at PhysicsWeb "Type-1.5 superconductor shows its stripes"
As well as the more recent story at Physorg.com
Our new theoretical works on this topic: E. Babaev J. Carlstrom, M. Speight "Type-1.5 superconductivity from interband Josephson coupling";
Johan Carlstrom, Egor Babaev, Martin Speight "Type-1.5 superconductivity in multiband systems: the effects of interband couplings"
Mihail Silaev, Egor Babaev Microscopic theory of type-1.5 superconductivity in multiband systems
For movies of vortex cluster formation in type-1.5 superconductors see http://people.umass.edu/garaud/NonPairwise.html
For a receint brief review see http://arxiv.org/abs/1110.2744
Vortex Cluster in type-1.5 superconductor: from our work with Johan and Julien
left and righ images shows drastically different behavior of two supercondicting components arrows shows the directions of the supercurrents:
"Super"-states of matter, such as superconductivity and superfluidity have attracted interest for almost a century. Four aggregate “super” states of matter are presently known: (i) superconducting electrons in metals, (ii) superfluid liquid He, (iii) superfluid vapours of ultracold atoms in traps, (iv) and possibly supersolid state of He. These experimental discoveries resulted into a breakthrough in our insight into the laws of microworld and even had impact well beyond condensed matter physics influencing e.g. the first discussions of the Higgs effect, chiral symmetry breakdown in QCD etc. A question to rise today is where the next experimental breakthrough in the field of quantum fluids might yet arise and whether the classification of quantum fluids into the above four classes can be extended: one of the topics of my recent research (see links to recent papers below) was on hydrogen which, as I proposed, at ultra high compression may form two band new types of “super” state of matter - the metallic superfluid and the superconducting superfluid. The pressures where this state is expected to form are extremely high but experimentally accessible: the required pressure is around four millions athmospheres while pressures exceeding three millions athmospheres have already been achieved in laboratories and most recent experiments aim at achieving pressures in the range of 10 millions athmospheres in not so distant future.
Background image: snapshot from Monte-Carlo simulations of vortex matter in the projected liquid metallic state of hydrogen (credit: Sudbo Smiseth and Smorgrav)
For popular description see e.g. the following media coverage in different languages of our recent papers Swedish "Nya teorier om metalliska supervätskor ger kvantfysiken nytt blod"
English: Physics World "Back to Square one for Superfluidity, PhysicsWeb "Metallic superfluid seen in computer" Nature Physics Research Highlight "Known unknowns in high-pressure hydrogen"
|Selected works me and
group (see CV for full
descriptiopn of my past
Prediction of metallic and superconducting superfluids in hydrogen and deuterium at ultrahigh pressures
Prediction of "type-1.5 superconductivity" and "semi-Meissner state", see also a bit more popular desciption and the recent overview
First discussions of paired states in multicomponent superconductors
First discussion of knotted solitons in condensed matter systems
Non-Meissner electrodynamics in multicomponent superconductors
Fractional Flux vortices and magnetic flux delocaliuzation and inversion in multicomponent superconductors
Violation of the Onsager-Feynman superflow quantization in superconducting superfluid
Spin-superfluidty in triplet superconductors
Introduction of vortex sublattice melting transition
A mechanism of giant reduction of coupling between handronic superfluids in neutron stars
First discussion of the pseudogap concept in high-energy physics related models
Introduction of a "hidden vortex lattice" concept in paired superfluids
Theory of proliferation of competing tangles of topological defects
Stable topological solitons in three-band superconductors
music and especially music by J.S. Bach
and weightlifting /