21 research outputs found
Thermopower of gapped bilayer graphene
We calculate thermopower of clean and impure bilayer graphene systems.
Opening a band gap through the application of an external electric field is
shown to greatly enhance the thermopower of bilayer graphene, which is more
than four times that of the monolayer graphene and gapless bilayer graphene at
room temperature. The effect of scattering by dilute charged impurities is
discussed in terms of the self-consistent Born approximation. Temperature
dependence of the thermopower is also analyzed.Comment: 8 pages, 5 figures; An inconsistency in the definitions of Eq.(17)
and (18) in version 1 is found and correcte
Quasilocal formalism and thermodynamics of asymptotically flat black objects
We study the properties of 5-dimensional black objects by using the
renormalized boundary stress-tensor for locally asymptotically flat spacetimes.
This provides a more refined form of the quasilocal formalism which is useful
for a holographic interpretation of asymptotically flat gravity. We apply this
technique to examine the thermodynamic properties of black holes, black rings,
and black strings. The advantage of using this method is that we can go beyond
the `thin ring' approximation and compute the boundary stress tensor for any
general (thin or fat) black ring solution. We argue that the boundary stress
tensor encodes the necessarily information to distinguish between black objects
with different horizon topologies in the bulk. We also study in detail the susy
black ring and clarify the relation between the asymptotic charges and the
charges defined at the horizon. Furthermore, we obtain the balance condition
for `thin' dipole black rings.Comment: v2 clarifications on the advantage of using quasilocal formalism for
black rings added, CQG versio
On the theory of irreversible processes
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1947.Vita.Includes bibliographical references (leaves 106-111).by Herbert B. Callen.Ph.D