Density functional theory of spin-polarized disordered quantum dots

Using density functional theory, we investigate fluctuations of the ground state energy of spin-polarized, disordered quantum dots in the metallic regime. To compare to experiment, we evaluate the distribution of addition energies and find a convolution of the Wigner-Dyson distribution, expected for noniteracting electrons, with a narrower Gaussian distribution due to interactions. The tird moment of the total distribution is independent of interactions, and so is predicted to decrease by a factor of 0.405 upon application of a magnetic field which transforms from the Gaussian orthogonal to the Gaussian unitary ensemble.Comment: 13 pages, 2 figure

Statistics of Coulomb blockade peak spacings for a partially open dot

We show that randomness of the electron wave functions in a quantum dot contributes to the fluctuations of the positions of the conductance peaks. This contribution grows with the conductance of the junctions connecting the dot to the leads. It becomes comparable with the fluctuations coming from the randomness of the single particle spectrum in the dot while the Coulomb blockade peaks are still well-defined. In addition, the fluctuations of the peak spacings are correlated with the fluctuations of the conductance peak heights.Comment: 13 pages, 1 figur

Finite temperature effects in Coulomb blockade quantum dots and signatures of spectral scrambling

The conductance in Coulomb blockade quantum dots exhibits sharp peaks whose spacings fluctuate with the number of electrons. We derive the temperature-dependence of these fluctuations in the statistical regime and compare with recent experimental results. The scrambling due to Coulomb interactions of the single-particle spectrum with the addition of an electron to the dot is shown to affect the temperature-dependence of the peak spacing fluctuations. Spectral scrambling also leads to saturation in the temperature dependence of the peak-to-peak correlator, in agreement with recent experimental results. The signatures of scrambling are derived using discrete Gaussian processes, which generalize the Gaussian ensembles of random matrices to systems that depend on a discrete parameter -- in this case, the number of electrons in the dot.Comment: 14 pages, 4 eps figures included, RevTe

Structure and collective dynamics of liquid sodium

The temperature variation of the longitudinal and transverse phonon frequencies of liquid sodium is investigated using the approach by Hubbard Beeby. The molecular dynamics simulation is used to generate the pair correlation function of liquid sodium at various temperatures viz. T = 378 K, 473 K, 573 K, and 723 K, with 672 particles. To describe the electron-ion interaction our own model potential is employed along with a recent local field correction function due to Sarkar et al. To evaluate the parameter of the potential the zero pressure condition has been applied. The present results of g(r) are in good agreement with available experimental findings. The computed g(r) are used to investigate the temperature variation of the collective dynamics of liquid sodium. The amplitudes of the peaks of the longitudinal and transverse frequencies are suppressed while the width of the propagation gap for the transverse sound waves decreases with an increase in temperature. The computed longitudinal and transverse sound velocities at these temperatures are found to be encouraging.За допомогою методу Габбарда-Бiбi дослiджувалась температурна залежнiсть повздовжньої та поперечної фононних частот рiдкого натрiю. Парна кореляцiйна функцiя рiдкого натрiю була запропонована при рiзних температурах, а саме T = 378 K, 473 K, 573 K та 723 K, застосовуючи метод молекулярної динамiки для 672 частинок. Опис електрон-iонної взаємодiї здiйснювався за допомогою запропонованого авторами модельного потенцiалу, доповненого функцiєю Серкара та iн., що описує поправку на локальне поле. Щоб оцiнити параметр потенцiалу, була застосована умова нульового тиску. Отриманi результати для g(r) добре узгоджуються з експериментальними даними. На основi обчисленої g(r) вивчалась температурна залежнiсть колективної динамiки рiдкого натрiю. Показано, що з пiдвищенням температури амплiтуди максимумiв повздовжньої i поперечної частот понижуються, а ширина пропагаторної щiлини для поперечних акустичних хвиль звужується

Clinical Relevance of Nontuberculous Mycobacteria, Oman

Little is known about the clinical relevance of nontuberculous mycobacteria (NTM) in the Arabian Peninsula. We assessed the prevalence and studied a random sample of isolates at a reference laboratory in Muscat, Oman. NTM cause disease in this region, and their prevalence has increased

Spin and interaction effects in quantum dots: a Hartree-Fock-Koopmans approach

We use a Hartree-Fock-Koopmans approach to study spin and interaction effects in a diffusive or chaotic quantum dot. In particular, we derive the statistics of the spacings between successive Coulomb-blockade peaks. We include fluctuations of the matrix elements of the two-body screened interaction, surface-charge potential, and confining potential to leading order in the inverse Thouless conductance. The calculated peak-spacing distribution is compared with experimental results.Comment: 5 pages, 4 eps figures, revise

District level baseline survey of family planning program in Uttar Pradesh: Jaunpur

Uttar Pradesh (UP) is the most populous state in India, with a population of 139 million, as of the 1991 census. The socioeconomic profile is characterized by relatively low levels of per capita income and literacy. Further, assessment of the family planning program and the demographic status as measured by Couple Protection Rate (CPR) and Mortality/Fertility rates mark UP as one of the country’s more demographically disadvantaged states. UP has a relatively higher Infant Mortality Rate, crude death rate, birth rate, and total fertility rate than the country as a whole, whereas CPR is much too low. The district of Jaunpur falls in the Eastern Region of the state, which on the whole is more disadvantaged than the Western Region. As noted in this report, no systematic surveys have ever been done to provide district-level estimates of fertility and mortality or CPR except in a few districts. The present survey is designed to provide valid estimates of vital rates and CPR at the district level and to fill gaps in the available information on several aspects related to the demographic situation and family planning program

District level baseline survey of family planning program in Uttar Pradesh: Jaunpur

Uttar Pradesh (UP) is the most populous state in India, with a population of 139 million, as of the 1991 census. The socioeconomic profile is characterized by relatively low levels of per capita income and literacy. Further, assessment of the family planning program and the demographic status as measured by Couple Protection Rate (CPR) and Mortality/Fertility rates mark UP as one of the country’s more demographically disadvantaged states. UP has a relatively higher Infant Mortality Rate, crude death rate, birth rate, and total fertility rate than the country as a whole, whereas CPR is much too low. The district of Jaunpur falls in the Eastern Region of the state, which on the whole is more disadvantaged than the Western Region. As noted in this report, no systematic surveys have ever been done to provide district-level estimates of fertility and mortality or CPR except in a few districts. The present survey is designed to provide valid estimates of vital rates and CPR at the district level and to fill gaps in the available information on several aspects related to the demographic situation and family planning program

District level baseline survey of family planning program in Uttar Pradesh: Gorakhpur

The state of Uttar Pradesh (UP) in India had a population of 139 million, as of the 1991 census. The socioeconomic profile is characterized by relatively low levels of per capita income and literacy. Further, assessment of the family planning program and the demographic status as measured by Couple Protection Rate (CPR) and Mortality/Fertility rates marks UP as one of the country’s more demographically disadvantaged states. UP has a relatively higher infant mortality rate, crude death rate, birth rate, and total fertility rate than the country as a whole, whereas CPR is much too low. The district of Gorakhpur falls in the Eastern Region of the state, which on the whole is more disadvantaged than the Western Region. As noted in this report, no systematic surveys have ever been done to provide district-level estimates of fertility and mortality or CPR except in a few districts. The present survey is designed to provide valid estimates of vital rates and CPR at the district level and to fill gaps in the available information on several aspects related to the demographic situation and family planning program