2,852 research outputs found
Entanglement between static and flying qubits in quantum wires
A weakly bound electron in a semiconductor quantum wire is shown to become
entangled with an itinerant electron via the coulomb interaction. The degree of
entanglement and its variation with energy of the injected electron, may be
tuned by choice of spin and initial momentum. Full entanglement is achieved
close to energies where there are spin-dependent resonances. Possible
realisations of related device structures are discussed
Band anticrossing in GaNxSb1âx
Fourier transform infrared absorption measurements are presented from the dilute nitride semiconductor GaNSb with nitrogen incorporations between 0.2% and 1.0%. The divergence of transitions from the valence band to Eâ and E+ can be seen with increasing nitrogen incorporation, consistent with theoretical predictions. The GaNSb band structure has been modeled using a five-band k·p Hamiltonian and a band anticrossing fitting has been obtained using a nitrogen level of 0.78 eV above the valence band maximum and a coupling parameter of 2.6 eV
Precision neuromodulation: Promises and challenges of spinal stimulation for multi-modal rehabilitation
Spinal cord injury results in multiple, simultaneous sensorimotor deficits. These include, but are not limited to, full or partial paralysis of muscles below the lesion, muscle spasms, spasticity, and neuropathic pain. Bowel, bladder, and sexual dysfunction are also prevalent. Yet, the majority of emerging spinal stimulation-based therapies focus on a single issue: locomotor rehabilitation. Despite the enormous potential of these translational advances to transform the lives of people living with spinal cord injury, meaningful recovery in other domains deemed critical priorities remains lacking. Here, we highlight the importance of considering the diverse patterns of neural transmission that underlie clinically similar presentations when developing spinal stimulation-based therapies. We also motivate advancement of multi-modal rehabilitation paradigms, which leverage the dense interconnectivity of sensorimotor spinal networks and the unique ability of electrical stimulation to modulate these networks to facilitate and guide simultaneous rehabilitation across domains
Never the twain shall meet: a critical appraisal of the combination of discourse and psychoanalytic theory in studies of men and masculinity
In recent years there has been a number of attempts by different researchers to study men and masculinity using a combination of discourse theory and psychoanalysis. The main reason for this development is the sense that, on its own, discourse theory provides an incomplete account of masculine subjectivity. Psychoanalysis is thought to be able to fill those gaps. In this paper I want to begin by reviewing these arguments. I will provide an outline of the alleged deficiencies in discursive approaches to men and masculinity before going on to examine some of the work that has attempted the above synthesis. What I aim to show is that, for a number of reasons, such attempts are bound to fail. Instead, I will argue that better progress can be made in studies of masculinity by remaining within the theoretical boundaries of Discursive Psychology
Band gap reduction in GaNSb alloys due to the anion mismatch
The structural and optoelectronic properties in GaNxSb1âx alloys (0<=x<0.02) grown by molecular-beam epitaxy on both GaSb substrates and AlSb buffer layers on GaAs substrates are investigated. High-resolution x-ray diffraction (XRD) and reciprocal space mapping indicate that the GaNxSb1âx epilayers are of high crystalline quality and the alloy composition is found to be independent of substrate, for identical growth conditions. The band gap of the GaNSb alloys is found to decrease with increasing nitrogen content from absorption spectroscopy. Strain-induced band-gap shifts, Moss-Burstein effects, and band renormalization were ruled out by XRD and Hall measurements. The band-gap reduction is solely due to the substitution of dilute amounts of highly electronegative nitrogen for antimony, and is greater than observed in GaNAs with the same N content
'Tumour volume' as a predictor of survival after resection of non-small-cell lung cancer (NSCLC)
Many factors have been individually related to outcome in populations of non-small-cell lung cancer (NSCLC) patients. Factors responsible for the outcome of an individual after surgical resection are poorly understood. We have examined the importance of 'tumour volume' in determining prognosis of patients following resection of NSCLC in a multivariate model. Cox's proportional hazard analysis was used to determine the relative prognostic significance of stage, patient age, gender, tumour cell-type, nodal score and estimated 'tumour volume' in 669 cases with NSCLC treated with surgical resection, of which 280 had died. All factors (except tumour cell-type, P = 0.33) were individually related to survival (P < 0.05). When examined together, survival time was significantly and independently related to 'tumour volume' and stage (P < 0.001), and other factors ceased to be significant. In cases with stage I or II tumours, risk of death was found to increase significantly with increasing estimated 'tumour volume' (23.8% relative increase in hazard to death per doubling of 'tumour volume', 95% confidence interval 13.2-35.2%, P < 0.001 stage I; P < 0.006 stage II). In cases with stage IIIa tumours this factor alone was the significant prognostic variable. In conclusion, an estimate of 'tumour volume' significantly improves prediction of prognosis for individual NSCLC patients with UICC stage I or II tumours
Shot noise reduction in quantum wires with "0.7 structure"
Shot noise reduction in quantum wires is interpreted within the model for the
''0.7 structure'' in the conductance of near perfect quantum wires [T. Rejec,
A. Ramsak, and J.H. Jefferson, Phys. Rev. B 62, 12985 (2000)]. It is shown how
the Fano factor structure is related to the specific structure of the
conductance as a consequence of the singlet--triplet nature of the resonances
with the probability ratio 1:3. An additional feature in the Fano factor,
related to the ''0.25 structure'' in conductance, is predicted.Comment: minor changes; to appear in Phys. Rev. B, Rapid. Comm. (2005
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