Electron screening and excitonic condensation in double-layer graphene systems

Physics – Condensed Matter – Strongly Correlated Electrons

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

4+ pages, 3 figures

Scientific paper

10.1103/PhysRevB.78.241401

We theoretically investigate the possibility of excitonic condensation in a system of two graphene monolayers separated by an insulator, in which electrons and holes in the layers are induced by external gates. In contrast to the recent studies of this system, we take into account the screening of the interlayer Coulomb interaction by the carriers in the layers, and this drastically changes the result. Due to a large number of electron species in the system (two projections of spin, two valleys, and two layers) and to the suppression of backscattering in graphene, the maximum possible strength of the screened Coulomb interaction appears to be quite small making the weak-coupling treatment applicable. We calculate the mean-field transition temperature for a clean system and demonstrate that its highest possible value $T_c^\text{max}\sim 10^{-7}\epsilon_F\lesssim 1 \text{mK}$ is extremely small ($\epsilon_F$ is the Fermi energy). In addition, any sufficiently short-range disorder with the scattering time $\tau \lesssim \hbar /T_c^\text{max}$ would suppress the condensate completely. Our findings renders experimental observation of excitonic condensation in the above setup improbable even at very low temperatures.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Electron screening and excitonic condensation in double-layer graphene systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Electron screening and excitonic condensation in double-layer graphene systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electron screening and excitonic condensation in double-layer graphene systems will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-651409

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.