Physics

Annealed Au-Assisted Epitaxial Growth of Si Nanowires: Control of Alignment and Density
The epitaxial growth of 1D nanostructures is of particular interest for future nanoelectronic devices such as vertical field-effect transistors because it directly influences transistor densities and 3D logic or memory architectures. Silicon nanowires (SiNWs) are a particularly important 1D nanomaterial because they possess excellent electronic and optical properties. What is more, the scalable...


Toward microfluidic design automation: a new system simulation toolkit for the in silico evaluation of droplet-based lab-on-a-chip systems
Miniaturization of biological and chemical assays in lab-on-a-chip systems is a highly topical field of research. The pressure-driven droplet-based microfluidic platform is a promising way to realize these miniaturized systems by expanding the capability of assays with special features that are unreached by traditional workflows. Full custom centric design of droplet-based microfluidic lab-on-a...
Particle focusing by AC electroosmosis with additional axial flow
ACEO-induced vortices have been used to manipulate fluids and particles for chemical and biochemical analysis in microscale systems. In such applications, a pressure-driven background flow is often applied to deliver the samples or particles into the target region. In the present study, the influence of an axial background flow on ACEO-induced vortices is experimentally investigated. An array o...


Analyzing the squeezed state generated by a twist deformation
The D1D5 CFT has provided a useful microscopic model for studying blackholes. The coupling in this theory is a twist deformation whose action on thevacuum generates a squeezed state. We give a new derivation of the expressionfor this squeezed state using the conformal Ward identity; this derivationprovides an insight into several features of the state. We also examine thesqueezed state in a con...
Remnant for all Black Objects due to Gravity's Rainbow
We argue that a remnant is formed for all black objects in gravity's rainbow. This will be based on the observation that a remnant depends critically on thestructure of the rainbow functions, and this dependence is a model independentphenomena. We thus propose general relations for the modified temperature andentropy of all black objects in gravity's rainbow. We explicitly check this tobe the c...


Imaginary parts and discontinuities of Wilson line correlators
We introduce a notion of position-space cuts of eikonal diagrams, the set ofdiagrams appearing in the perturbative expansion of the correlator of a set ofstraight semi-infinite Wilson lines. The cuts are applied directly to theposition-space representation of any such diagram and compute its imaginarypart to the leading order in the dimensional regulator. Our cuttingprescription thus defines a ...
Pure connection formalism for gravity: Recursion relations
In the gauge-theoretic formulation of gravity the cubic vertex becomes simpleenough for some graviton scattering amplitudes to be computed usingBerends-Giele-type recursion relations. We present such a computation for thecurrent with all same helicity on-shell gravitons. Once the recursion relationis set up and low graviton number cases are worked out, a natural guess for thesolution in terms o...

Graviton modes in multiply warped geometry
The negative results in the search for Kaluza-Klein graviton modes at theLHC, when confronted with the discovery of the Higgs, has been construed tohave severely limited the efficacy of the Randall-Sundrum model as anexplanation of the hierarchy problem. We show, though, that the presence ofmultiple warping offers a natural resolution of this conundrum throughmodifications in both the graviton ...
Non-relativistic Josephson Junction from Holography
We construct a Josephson junction in non-relativistic case with a Lifshitzgeometry as the dual gravity. We investigate the effect of the Lifshitz scalingin comparison with its relativistic counterpart. The standard sinusoidalrelation between the current and the phase difference is found for variousLifshitz scalings characterised by the dynamical critical exponent. We alsofind the exponential de...

Baryons in the Sakai-Sugimoto model in the D0-D4 background
The baryon spectrum in the Sakai-Sugimoto model in the D4 background withsmeared D0 charges is studied. We follow the instanton description of baryonsby Hata et al.[Prog. Theor. Phys. 117, 1157]. The background corresponds to anexcited state with nonzero glue condensate $langle {rm tr} (F_{munu}tildeF^{munu})rangle$ which is proportional to the D0 charge density. The baryonsize shrinks when we ...
The Quantum Information of Cosmological Correlations
It has been shown that the primordial perturbations sourced by inflation aredriven to classicality by unitary evolution alone. However, their coupling withthe environment such as photons and subsequent decoherence renders thecosmological correlations quantum, losing primordial information in theprocess. We argue that the quantumness of the resulting cosmologicalcorrelations is given by quantum ...

Graphene transparency in weak magnetic fields
We carry out an explicit calculation of the vacuum polarization tensor for aneffective low-energy model of monolayer graphene in the presence of a weakmagnetic field of intensity $B$ perpendicularly aligned to the membrane. Byexpanding the quasiparticle propagator in the Schwinger proper timerepresentation up to order $(eB)^2$, where $e$ is the unit charge, we find anexplicitly transverse tenso...
From algebraic curve to minimal surface and back
We derive the Lax operator for a very large family of classical minimalsurface solutions in $AdS_3$ describing Wilson loops in $mathcal{N}=4$ SYMtheory. These solutions, constructed by Ishizeki, Kruczenski and Ziama, areassociated with a hyperellictic surface of odd genus. We verify that thealgebraic curve derived from the Lax operator is indeed none-other than thishyperelliptic surface.
Interactions of Charged Spin-2 Fields
In light of recent progress in ghost-free theories of massive gravity andmulti-gravity, we reconsider the problem of constructing a ghost-free theory ofan interacting spin-2 field charged under a U(1) gauge symmetry. Our startingpoint is the theory originally proposed by Federbush, which is essentiallyFierz-Pauli generalized to include a minimal coupling to a U(1) gauge field. Weshow the Federb...
Octonion generalization of Pauli and Dirac matrices
Starting with octonion algebra and its 4 × 4 matrix representation, we have made an attempt to write the extension of Pauli's matrices in terms of division algebra (octonion). The octonion generalization of Pauli's matrices shows the counterpart of Pauli's spin and isospin matrices. In this paper, we also have obtained the relationship between Clifford algebras and the division algebras, i.e. ...