Joining-splitting interaction of non-critical string

The joining--splitting interaction of non-critical bosonic string is analyzed in the light-cone formulation. The Mandelstam method of constructing tree string amplitudes is extended to the bosonic massive string models of the discrete series. The general properties of the Liouville longitudinal excitations which are necessary and sufficient for the Lorentz covariance of the light-cone amplitudes are derived. The results suggest that the covariant and the light-cone approach are equivalent also in the non-critical dimensions. Some aspects of unitarity of interacting non-critical massive string theory are discussed.Comment: 38 pages, 4 embedded figures, discussion in the Introduction clarified, Appendix D and some material from Section 5 remove

Phonon-assisted relaxation between hole states in quantum dot molecules

We study theoretically phonon-assisted relaxation and inelastic tunneling of holes in a double quantum dot. We derive hole states and relaxation rates from kp Hamiltonians and show that there is a finite distance between the dots where lifetimes of hole states are very long which is related to vanishing tunnel coupling. We show also that the light hole admixture to hole states can considerably affect the hole relaxation rates even though its magnitude is very small

Topologically confined states at corrugations of gated bilayer graphene

We investigate the electronic and transport properties of gated bilayer graphene with one corrugated layer, which results in a stacking AB/BA boundary. When a gate voltage is applied to one layer, topologically protected gap states appear at the corrugation, which reveal as robust transport channels along the stacking boundary. With increasing size of the corrugation, more localized, quantum-well-like states emerge. These finite-size states are also conductive along the fold, but in contrast to the stacking boundary states, which are gapless, they present a gap. We have also studied periodic corrugations in bilayer graphene; our findings show that such corrugations between AB- and BA-stacked regions behave as conducting channels that can be easily identified by their shape

Light-cone formulation and spin spectrum of non-critical fermionic string

A free fermionic string quantum model is constructed directly in the light-cone variables in the range of dimensions $1<d<10$. It is shown that after the GSO projection this model is equivalent to the fermionic massive string and to the non-critical Rammond-Neveu-Schwarz string. The spin spectrum of the model is analysed. For $d=4$ the character generating functions is obtained and the particle content of first few levels is numerically calculated.Comment: 13 page

D.A.F. de Sade – "Divine Marquis" or demolisher of the ideas of Enlightment

The paper provides a brief outline of the major elements that made up the foundations for the political thought of Marquis D. A. F. de Sade. The author of the paper believes that these elements have not been sufficiently presented in the Polish historiography of political doctrines. The Marquis, being deeply anchored in the Enlightenment ideas and stylistics, was simultaneously the thinker who questioned a remarkable number of elements of these ideas. What he challenged were in particular: the previous descriptions of nature, natural state, location and status of the human being, social contract and the concept of State and law. By questioning these concepts he indirectly challenged also the major articles of the Declaration of Rights of Man and Citizen. His political concepts are detectable in most of his literary production and therefore the author of the paper treats what is detectable as a certain whole which perhaps is not fully consistent of morality and law, both those of ancien régime as well as those promoted by too idealistic concepts of the pre-revolutionary era. An interesting example of the originality of his way of political thinking was his attempt to present to the reader the two extremely different socio-constitutional models – that of classical Utopia and that of Anti-utopia – as included in one literary production. The essay is concluded with a brief attempt at the summarizing and assessing of the discussed concepts as viewed against our present-day reception of de Sade’s production and his location in the history of political thought

Electronic structure of defected trilayer graphene

Wersja opublikowana DOI: https://doi.org/10.1080/00268976.2021.2013554Gated trilayer graphene shows energy gap and three topologically protected gaplessstates when the stacking order changes from ABC to CBA. Here we such a trilayer, but with a part of the internal layer cut and removed forming a region in trilayer built of only two not connected single graphene layers. We demonstrate that the electronic structure of this region is almost the same as of the gated trilayer. Curiously, the topological gapless states that appear due to difference in the stacking order of the adjacent trilayers localize mostly in these single graphene layers. Thus, strong disorder in the internal layer of gated trilayer graphene does not lead to destruction of its fundamental electronic properties

Static Quark Potential from the Polyakov Sum over Surfaces

Using the Polyakov string ansatz for the rectangular Wilson loop we calculate the static potential in the semiclassical approximation. Our results lead to a well defined sum over surfaces in the range $1<d<25$.Comment: 17 pages, (with a TeX error on the title page corrected - nothing else changed

Interface States in Carbon Nanotube Junctions: Rolling up graphene

We study the origin of interface states in carbon nanotube intramolecular junctions between achiral tubes. By applying the Born-von Karman boundary condition to an interface between armchair- and zigzag-terminated graphene layers, we are able to explain their number and energies. We show that these interface states, costumarily attributed to the presence of topological defects, are actually related to zigzag edge states, as those of graphene zigzag nanoribbons. Spatial localization of interface states is seen to vary greatly, and may extend appreciably into either side of the junction. Our results give an alternative explanation to the unusual decay length measured for interface states of semiconductor nanotube junctions, and could be further tested by local probe spectroscopies