21 research outputs found
Shaping electron wave functions in a carbon nanotube with a parallel magnetic field
A magnetic field, through its vector potential, usually causes measurable
changes in the electron wave function only in the direction transverse to the
field. Here we demonstrate experimentally and theoretically that in carbon
nanotube quantum dots, combining cylindrical topology and bipartite hexagonal
lattice, a magnetic field along the nanotube axis impacts also the longitudinal
profile of the electronic states. With the high (up to 17T) magnetic fields in
our experiment the wave functions can be tuned all the way from "half-wave
resonator" shape, with nodes at both ends, to "quarter-wave resonator" shape,
with an antinode at one end. This in turn causes a distinct dependence of the
conductance on the magnetic field. Our results demonstrate a new strategy for
the control of wave functions using magnetic fields in quantum systems with
nontrivial lattice and topology.Comment: 5 figure
An infantâled approach to complementary feeding is positively associated with language development
The timing and strategy with which parents first introduce their infants to solid foods may be an important predictor of subsequent developmental outcomes. Recent years have seen a decline in the prevalence of traditional parentâled feeding of soft, purĂ©ed food and a rise in the prevalence of infantâled complementary feeding. Although there has been some research espousing the benefits of infantâled complementary feeding for improving food fussiness and selfâregulation, there has been little exploration of this approach that may impact on other developmental outcomes in children. The current study explores whether aspects of the infantâled approach, specifically the child eating unaided and consuming finger foods and eating with the family, are related to child language outcomes. One hundred thirty one parents of children aged 8â24 months completed questionnaires about their approach to complementary feeding, their current feeding practices, their child's experiences with family foods and child language comprehension/production. The findings suggest that an approach to complementary feeding which promotes infant autonomy in feeding (i.e., eating finger foods rather than purĂ©ed foods) and consuming more family foods is related to more advanced child language production and comprehension. Specifically, the prevalence of eating family foods mediated the relationship between eating unaided at the onset of the complementary feeding period and later language outcomes. This study is the first to find a significant relationship between different approaches to introducing solid foods and child language outcomes and these findings highlight the potential for different complementary feeding approaches to influence behaviour beyond mealtimes