35 research outputs found
Twist tori and pseudo toric structures
Twist tori are examples of exotic monotone lagrangian tori, presented in [1].
This tree of examples grew up over the first one --- the torus , constructured in [2] and [3]. On the other hand, in [4] and [5] we
proposed a new structure which generalizes the notion of toric structure. One
calls this generalization pseudo toric structure, and several examples were
given which show that certain toric symplectic manifolds can carry the structre
and that certain non toric symplectic manifolds do the same. Below we show that
any twist torus , defined in [1], can be
constructed via pseudo toric considerations. Due to this one can explicitly
show that every is displaceable
Charge relaxation resistance in the Coulomb blockade problem
We study the dissipation in a system consisting of a small metallic island
coupled to a gate electrode and to a massive reservoir via single tunneling
junction. The dissipation of energy is caused by a slowly oscillating gate
voltage. We compute it in the regimes of weak and strong Coulomb blockade. We
focus on the regime of not very low temperatures when electron coherence can be
neglected but quantum fluctuations of charge are strong due to Coulomb
interaction. The answers assume a particularly transparent form while expressed
in terms of specially chosen physical observables. We discovered that the
dissipation rate is given by a universal expression in both limiting cases.Comment: 21 pages, 12 figure
Quantum transport in a normal metal/odd-frequency superconductor junction
Recent experimental results indicate the possible realization of a bulk
odd-frequency superconducting state in the compounds CeCuSi, and
CeRhIn. Motivated by this, we present a study of the quantum transport
properties of a normal metal/odd-frequency superconductor junctions in a search
for probes to unveil the odd-frequency symmetry. From the Eliashberg equations,
we perform a quasiclassical approximation to account for the transport
formalism of an odd-frequency superconductor with the Keldysh formalism.
Specifically, we consider the tunneling charge conductance and tunneling
thermal conductance. We find qualitatively distinct behaviour in the
odd-frequency case as compared to the conventional even-frequency case, in both
the electrical and thermal current. This serves as a useful tool to identify
the possible existence of a bulk odd-frequency superconducting state.Comment: 7 pages, 3 figures. Accepted for publication in Physical Review
Gromov compactness for holomorphic discs with totally real boundary conditions
We prove that a sequence of holomorphic discs with totally real boundary
conditions has a subsequence that Gromov converges to a stable holomorphic map
of genus zero with connected boundary provided that the sequence is bounded and
has bounded energy.Comment: To appear in J. Fixed Point Theory App