63 research outputs found
Radio frequency spectroscopy of the attractive Hubbard model in a trap
Attractive interaction between fermions can lead to pairing and superfluidity
in an optical lattice. In contrast to the `continuum', on a lattice the trap
induced density variation can generate a non monotonic profile of the pairing
amplitude, and completely modify the spectral signatures of any possible
pseudogap phase. Using a tool that fully captures the inhomogeneity and strong
thermal fluctuations, we demonstrate how the crucial radio frequency signatures
of pairing are `inverted' in a trapped attractive fermion lattice compared to
the traditional continuum case. These features would be central in interpreting
any spectroscopic hint of fermion pairing and superfluidity.Comment: this article supersedes arXiv:1104.491
Evidence of linear and cubic Rashba effect in non-magnetic heterostructure
The LaAlO3/KTaO3 system serves as a prototype to study the electronic
properties that emerge as a result of spin-orbit coupling. In this article, we
have used first-principles calculations to systematically study two types of
defect-free (0 0 1) interfaces, which are termed as Type-I and Type-II. While
the Type-I heterostructure produces a two-dimensional electron gas, the Type-II
heterostructure hosts an oxygen-rich two-dimensional hole gas at the interface.
Furthermore, in the presence of intrinsic spin-orbit coupling, we have found
evidence of both cubic and linear Rashba interactions in the conduction bands
of the Type-I heterostructure. On the contrary, there is spin-splitting of both
the valence and the conduction bands in the Type-II interface, which are found
to be only linear Rashba type. Interestingly, the Type-II interface also
harbours a potential photocurrent transition path, making it an excellent
platform to study the circularly polarized photogalvanic effect
Rashba splitting in polar-nonpolar sandwich heterostructure : A DFT Study
In this study, we employ density functional theory (DFT) based
first-principles calculations to investigate the spin-orbit effects in the
electronic structure of a polar-nonpolar sandwich heterostructure namely
LAO/STO/LAO. Our focus on the Ti-3d bands reveals an
inverted ordering of the STO- orbital near the n-type interface,
consistent with earlier experimental work. In contrast, toward the p-type
interface, the orbital ordering aligns with the natural ordering of STO
orbitals, influenced by crystal field splitting. Interestingly, we have found a
strong inter-orbital coupling between and orbital, which has not
been reported earlier in based 2D system. Additionally, our
observations highlight that the cubic Rashba splitting in this system surpasses
the linear Rashba splitting, contrary to experimental findings. This
comprehensive analysis contributes to a refined understanding of the role of
orbital mixing in Rashba splitting in the sandwich oxide heterostructures
Long range correlations in a 97% excitonic one-dimensional polariton condensate
We report on the realization of an out-of-equilibrium polariton condensate
under pulsed excitation in a one-dimensional geometry. We observe macroscopic
occupation of a polaritonic mode with only 3% photonic fraction, and a nature
strikingly close to that of a bare exciton condensate. With the help of this
tiny photonic fraction, the condensate is found to display first-order
coherence over distances as large as 10 microns. Based on a driven-dissipative
mean field model, we find that the correlations length is limited by the
effects of a shallow disorder under non-equilibrium conditions.Comment: 5 pages, 3 figure
Electrical conductivity degradation of fatigued carbon black reinforced natural rubber composites: Effects of carbon nanotubes and strain amplitudes
The fatigue of rubber products is usually accompanied by undesirable transformation in their properties. The present work was dedicated to the investigation of consequences of fatigue loading on volume electric conductivity of natural rubber (NR) reinforced with 30 phr of fillers composed from various weight combinations of carbon nanotubes (CNTs) and carbon black (CB). Special attention was paid to study the influence of CNTs content on residual electric conductivity and a possible mechanism of fatigue driven rearrangement of hybrid filler network inside of rubber matrix was propounded forward. An increase in the CNTs content over the complete range of concentrations, enhanced the conductivity of fabricated samples up to two orders of magnitude in comparison to rubber compounds without CNTs. All the samples were subjected to harmonic sinusoidal loading at a frequency of 5 Hz up to 10(5) loading cycles at three different strains of 0.1, 0.25 and 0.5. Despite very little transformation in the polymer matrix, fatigue caused a progressive degradation of conductivity with an increase in applied strain. It was also found that with the addition and a subsequent increase in the concentration of CNTs, the undesirable reduction of conductivity was significantly arrested. This novel finding added another number to the list of the outstanding properties of CNTs.Operational Program Research and Development for Innovations - European Regional Development FundEuropean Union (EU); national budget of the Czech Republic [CZ.1.05/2.1.00/19.0409]; Ministry of Education, Youth and Sports of the Czech Republic - Program NPU I [LO1504]; [IGA/CPS/2019/001
Influence of non-genetic factors on body weight in Black Bengal goats maintained under field condition
Data recorded on 10,148 Black Bengal kids maintained at farmer’s herds in different
districts of West Bengal from 2008 to 2019 were used to study the effect of non-genetic factors on
body weight from birth to 12 months of age. The data were analysed using least squares technique.
The effect of year of kidding on body weight of Black Bengal kids at different ages was significant
(p<0.05). Influence of season and parity of the dam had significant effect (p<0.05) on body weight
of kids from birth to 6 months of age. Sex of the kid significantly influenced body weight from birth to
12 months of age. Effect of types of birth on body weight at different ages up to 12 months of age of
Black Bengal kids were significant (p<0.05). Significantly higher body weight at birth was recorded
in single born kid, followed by twin, triplets and so on
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