Nano-Engineering Defect Structures on Graphene

We present a new way of nano-engineering graphene using defect domains. These regions have ring structures that depart from the usual honeycomb lattice, though each carbon atom still has three nearest neighbors. A set of stable domain structures is identified using density functional theory (DFT), including blisters, ridges, ribbons, and metacrystals. All such structures are made solely out of carbon; the smallest encompasses just 16 atoms. Blisters, ridges and metacrystals rise up out of the sheet, while ribbons remain flat. In the vicinity of vacancies, the reaction barriers to formation are sufficiently low that such defects could be synthesized through the thermally activated restructuring of coalesced adatoms.Comment: 4 pages, 5 figure

Engineering and Manipulating Exciton Wave Packets

When a semiconductor absorbs light, the resulting electron-hole superposition amounts to a uncontrolled quantum ripple that eventually degenerates into diffusion. If the conformation of these excitonic superpositions could be engineered, though, they would constitute a new means of transporting information and energy. We show that properly designed laser pulses can be used to create such excitonic wave packets. They can be formed with a prescribed speed, direction and spectral make-up that allows them to be selectively passed, rejected or even dissociated using superlattices. Their coherence also provides a handle for manipulation using active, external controls. Energy and information can be conveniently processed and subsequently removed at a distant site by reversing the original procedure to produce a stimulated emission. The ability to create, manage and remove structured excitons comprises the foundation for opto-excitonic circuits with application to a wide range of quantum information, energy and light-flow technologies. The paradigm is demonstrated using both Tight-Binding and Time-Domain Density Functional Theory simulations.Comment: 16 figure

Combining presleep cognitive training and REM-sleep stimulation in a laboratory morning nap for lucid dream induction.

Previous experiments combining cognitive techniques and sleep disruption have been relatively successful in inducing at-home lucid dreams (LD) over training periods of 1 week or more. Here, we induce LD in a single laboratory nap session by pairing cognitive training with external stimulation. Participants came to the laboratory at 7:30 a.m. or 11:00 a.m. and during polysomnography setup were provided with information about lucid dreaming. For 20 min prior to sleep the experimenter played alternating audio and visual cues at 1-min intervals. Participants were instructed to practice a mental state of critical self-awareness, observing their thoughts and experiences each time they noticed a cue. This procedure associated the cues with the trained mental state. Subsequently, participants were allowed 90 min to nap, and the audio and visual cues were presented during REM sleep to activate self-awareness in dreams and elicit lucidity. A control group followed the same procedure but was not cued during sleep. All participants were instructed to signal their lucidity by looking left and right 4 times (LR signal). Signal-verified lucid dreams (SVLDs) qualified as dreams in which the LR signal was observed and the participant reported becoming lucid. Across the 2 nap times, this protocol induced SVLDs in 50% of cued participants. In the absence of cueing during sleep, participant SVLD rate was 17%. Of note, 3 successful participants had never before experienced a LD, suggesting this protocol may be effective across the general population. Implications of this Targeted Lucidity Reactivation protocol for nightmare treatment are discussed

Romance for Oboe and Piano

The breadth of contemporary music includes an expansion of harmonies, genres, instrumentation, and techniques. With all these options available today, many composers still feel it is important to connect with the audience on a personal and expressive level. The submitted piece Romance for Oboe and Piano attempts to do just that. Romance features post-tonal materials of modern compositional writing. Some of the compositional techniques included in Romance are octatonicism, more complex chord structures, pandiatonicism, modal, pentatonic, and whole tone scales. At the beginning of Romance, the piano and oboe are treated as two separate entities but as the work progresses, they gradually merge together into a warm, fervent, and unbreakable relationship. To take it a step further, and on a more personal note, this piece is a declaration of my love for my wife (and oboist) Tracy. Many composers of the 19th–century (the “Romantic” period) sought to create strong emotional bonds with their audience. The desired end result of Romance is one in which materials of modern composition coalesce into a unique, cogent musical work exhibiting the same emotive and impassioned feelings frequently found in music of the “Romantic” era

Embedded Ribbons of Graphene Allotropes: An Extended Defect Perspective

Four fundamental dimer manipulations can be used to produce a variety of localized and extended defect structures in graphene. Two-dimensional templates result in graphene allotropes, here viewed as extended defects, which can exhibit either metallic or semiconducting electrical character. \emph{Embedded allotropic ribbons}--i.e. thin swaths of the new allotropes--can also be created within graphene. We examine these ribbons and find that they maintain the electrical character of their parent allotrope even when only a few atoms in width. Such extended defects may facilitate the construction of monolithic electronic circuitry.Comment: 24 pages, 21 figure