Thursday, August 30, 2007

Ilya Vekhter: "Probing anisotropic superconductivity with magnetic field"


Ilya presented his work done with Anton Vorontsov on extracting the nodal structure of an order parameter by applying a magnetic field in varying directions and predicting what the zero-bias density of states averaged over the vortex unit cell looks like as a function of field direction. Starting with an experimental overview, in particular specific heat and heat conductivity measurements were singled out for testing nodal quasiparticles. Based on work by Volovik '93, the local density was calculated in the Doppler-shift approximation and averaged over the vortex unit cell. Ilya pointed out that although many experiments contain information about the presence or absence of nodes, not so many tell where in the Brillouin zone the nodes are situated. In order to tackle this problem, Ilya presented studies where a magnetic field is rotated and the averaged zero-bias DOS is monitored.


Question by Dirk Morr: is the field in plane? Answer by Ilya: we do not assume any Josephson vortex structures to be present, all vortices are usual Abrikosov vortices.


Ilya then draw a picture with an oscillating behavior of the averaged N(w=0) as a function of field angle, with minima where the field is parallel to the node. Ilya then pointed out contradicting experimental findings for CeCoIn_5, with nodes either consistent with a d_x^2-y^2 or a d_xy order parameter. Ilya suggested that this can be explained by a more careful study in the high-field region. Solving Eilenberger-Larkin-Ovchinnikov equations employing the Brandt-Pesch-Teward approximation again the averaged zero-bias DOS was calculated, this time also covering the high field region. Ilya summarized the results of these calculations in a H-T phase diagram, with a low-T low-field region showing minima in N(w=0) as tested by C/T when the field points in nodal direction, another not so interesting region near T_c, and an 'inverted' region in the rest of the phase diagram where a maximum occurs in C/T as function of field direction when the field points in nodal direction.


Q: Hartmut Monien asked if subdominant order parameters in the vortex core regions would change the results. Ilya answered that he does not think that this happenes in the materials that were studied.


Q: Ben Powell was interested in the role of pancake vortices, however this was beyond the model Ilya was considering.

20 comments:

Invertir en oro said...

Thanks for sharing this info because is very good and i like to post like this.

Niconot quit smoking medicine said...

Anisotropic superconductivity with Magnetic field, seems to be a very heavy subject to work on.

Ideas de negocios said...

Thanks for taking the time to discuss this, but I am firmly convinced of this and love to learn more about the subject. If possible, acquire knowledge, would you update your blog with more information? It is very helpful to me

Vimax penis growth pills said...

In order to tackle this problem, Ilya presented studies where a magnetic field is rotated and the averaged zero-bias DOS is monitored.

Vimax penis enlargement pills said...

People do have a lot of things to work on despite the fact that there needs to be more improvement.

Premature ejaculation pills review said...

In the earth there's no material that can resist the temperature of the plasma....

Male Extra enhancement pills said...

Thank you for this post. I have been on a research kick and pulling up everything I can on Superconductivity. This was a very well written post! You explained a lot in such a short post. Thanks. I will definitely look forward to hear more from you soon.

hcg said...

wow great i have read many articles about this topic and everytime i learn something new i dont think it will ever stop always new info , Thanks for all of your hard work!

hcg buy said...

The earth there's no material that can resist the temperature of the plasma and how to burn 3500 to 4000 calories of stored fat and LOSING UP 1 to 2 POUNDS A DAY...

NeosizeXL increase penis size pills said...

Averaged zero-bias DOS is monitored ! How it could be ! well Ilya best of luck.

Best penis enlargement supplement said...

Solving Eilenberger-Larkin-Ovchinnikov equations employing the Brandt-Pesch-Teward approximation again the averaged zero-bias DOS was calculated.

saim said...

thanks for sharing such a nice info its very much impressive.



natural supplements

Weak erection pills said...

Proving the superconductivity of the magnetic field is the most important fact rather than other equation.

19PFL3505D said...

Anton Vorontsov is a smart man.

Natural penis growth pills said...

the Brandt-Pesch-Teward approximation again the averaged zero-bias DOS was calculated, this time also covering the high field region.

Vimax penis enlargement pills said...

That's good work by Ilya Vekhter. Thanks for sharing this.

All Top models 2012 said...

Many many thanks for sharing this information with us. I want to congratulate you because you are doing a great job here.

Make iPhone App said...

That's really massive exposure post and I must admire you in this regard.

Unknown said...

Vimax Australia
Vimax Singapore
Vimax Canada
Vimax Trial
Vimax Bulgaria
Vimax Ceska
Vimax Chile
Vimax Danmark
Vimax Deutschland
Vimax Espana
Vimax Greece
Vimax India
Vimax Ireland
Vimax Magyarorszagon
Vimax Mexico
Vimax Nederland
Vimax Newzealand
Vimax Norway
VigRx Plus
VigRx Plus
VigRx Plus
VigRx Plus
Vimax Peru
Vimax Polska
Vimax Romania
Vimax Swedeen
Vimax Uruguay
Vimax Venezuela
Vimax Extender
Vimax Australia
Vimax Singapore
Vimax Canada
Vimax

aghustramadhant said...

Vimax penis enlargement herbal medicines are very effective for men and a leading worldwide because of proven efficacy
Vimax pills

http://buyvimaxherbal.com