Detection and measurement of the Dzyaloshinskii-Moriya interaction in double quantum dot systems

Spins in quantum dots can act as the qubit for quantum computation. In this context we point out that spins on neighboring dots will experience an anisotropic form of the exchange coupling, called the Dzyaloshinskii-Moriya (DM) interaction, which mixes the spin singlet and triplet states. This will have an important effect on both qubit interactions and spin-dependent tunneling. We show that the interaction depends strongly on the direction of the external field, which gives an unambiguous signature of this effect. We further propose a new experiment using coupled quantum dots to detect and characterize the DM interaction.Comment: Updated version. Submitted to Physical Review

Universal Quantum Computation in a Neutral Atom Decoherence Free Subspace

In this paper, we propose a way to achieve protected universal computation in a neutral atom quantum computer subject to collective dephasing. Our proposal relies on the existence of a Decoherence Free Subspace (DFS), resulting from symmetry properties of the errors. After briefly describing the physical system and the error model considered, we show how to encode information into the DFS and build a complete set of safe universal gates. Finally, we provide numerical simulations for the fidelity of the different gates in the presence of time-dependent phase errors and discuss their performance and practical feasibility.Comment: 7 pages, 8 figure

Psychological Well-Being Among the Gender Wise Category of Users in terms of Library Anxiety at Centrally Funded Universities of Assam, India

The purpose of this paper is to assess the mental health of the male and female library users of the centrally funded university libraries of Assam in Northeast India i.e., Assam University and Tezpur University. The study has been conducted in the context of library anxiety while finding information by both the category of users to identify the shortcomings in the library system and also to suggest the remedies. Survey method has been adopted to conduct the research study. A structured questionnaire has been designed and distributed among randomly selected users. The statements developed by Sharon L Bostick (1992) which is known as the Library Anxiety Scale have been applied. Library anxiety has been measured with the help of the scores proposed by Anwar, Al-Kandari, and Al-Qallaf (2004). It is evident that Library anxiety exists in both Assam University and Tezpur University. Library anxiety is more in terms of library resources and library environment. Among the gender category, library anxiety is found to be at an extreme level among female users. This research study, being the first of this kind helped in finding out the library anxiety by adopting the library anxiety scale

Exploring Prevalence and Psycho-Social factors of Library Anxiety among the Student Category of Users based on University affiliations

An outright fear of using library facilities has been observed among students which can hinder academic productivity among students. Library anxiety poses as a psychological barrier in effective use of library resources. Research suggests us to delve deeper in the library perspectives in order to unearth possible causes of anxiety associated with it. The present study is a descriptive cross-sectional design intended to examine library anxiety among the students\u27 category of library users in Assam\u27s state universities; along with investigation of probable psycho-social reasons for such an anxiety. For the study, a sample size of 160 (Gauhati University = 80 and Dibrugarh University = 80) was selected using the Purposive sampling technique. The Bostick’s Library anxiety scale and a self-constructed questionnaire were administered and simple frequencies, summarized figures and chi-square was applied to achieve the objectives. Results revealed that no significant difference exists in the prevalence of library anxiety among the students on the basis of university affiliations. It was also found that existence of pre-conceived social and exam anxiety, along with difficulties in academic planning and learning were detected as major psycho-social causes for higher levels of anxiety

FREE RADICAL MEDIATED DISEASES AND THEIR PREVENTION : AN AYURVEDIC PERSPECTIVE

Free radical production occurs continuously in all cells as part of normal cellular function. However, excess free radical production originating from endogenous or exogenous sources might play a role in many diseases. Antioxidants prevent free radical induced tissue damage by preventing the formation of radicals, scavenging them, or by promoting their decomposition. The disease preventive and health promotive approach of 'Ayurveda', which takes into consideration the whole body, mind and spirit while dealing with the maintenance of health, promotion of health and treating ailments is holistic and finds increasing acceptability in many regions of the world. Ancient Ayurvedic physicians had developed certain dietary and therapeutic measures to arrest/delay ageing and rejuvenating whole functional dynamics of the body system. This revitalization and rejuvenation is known as the 'Rasayan chikitsa' (rejuvenation therapy). Rasayana is intended in classical Ayurveda as an effective tool to synthesize the excellent quality of Dhatu that entails the prevention and alleviation of senility and diseases. Experimental studies done on various Rasayana drugs prove that they have immune stimulant, antioxidant, adaptogenic and anti-stress properties. Rasayana drugs consist of the substances which are rich in Vitamin C, Vitamin E, Beta carotene, riboflavin. So these substances are capable of counteracting the damaging effect of oxidation by working as anti-oxidants & prevent aging process. Over about 100 disorders like rheumatoid arthritis, hemorrhagic shock, CVS disorders, cystic fibrosis, metabolic disorders, neurodegenerative diseases, gastrointestinal ulcerogenesis and AIDS have been reported as reactive oxygen species mediated. In this review, the role of free radicals in these diseases has been briefly reviewed. 'Rasayana' plants with potent antioxidant activity have been reviewed for their traditional uses, and mechanism of antioxidant action

Cultural Intelligence as a Correlate of Academic Performance among the students of Masters in Library and Information Science

A library is a perfect multi-cultural setting, where people from all ethnic backgrounds come together to access information. In this context, it becomes very vital for future library professionals to consider cultural skills as a tool kit to identify and manage varied cultural characteristics. Academic performance of Library science students might be an effective indicator of their being a potential professional in library settings in the future. So the objective of the paper was to investigate whether academic performance of library students was significantly predicted by Cultural Intelligence and certain demographic variables of students studying in the Department of Library Science and Information from the three prominent universities of Assam. For the study, all the 66 students from the three universities were selected, out of which 61 students responded to the survey. Data was collected using Cultural Quotient Scale, developed by Soon Ang and Van Dyne. The results of regression analysis were found to be statistically significant in case of both Gauhati and Dibrugarh universities. The motivational and behavioral components of cultural intelligence, along with demographic characteristics like gender and work experience emerged as strong predictors of academic performance among the students of Gauhati University. The cognitive, metacognitive and behavioral components of cultural intelligence, along with demographic characteristics like possession of professional qualification and place of residence were found to be strong predictors of academic performance among the students of Dibrugarh University

Size-dependent bond dissociation enthalpies in single-walled carbon nanotubes

We report the bond dissociation enthalpy (BDE) and the local electronic properties of Single-Walled Carbon Nanotubes (SWCNT) using density functional theory. Our analysis shows that there is a strong size-dependence of the BDE of these SWCNTs, which is inversely proportional to the radius-squared (1/r2) and the length (1/l) of SWCNT. We derive quantitative relationships from which the BDE can be calculated as a function of size and radius of the SWCNT. We find that the BDE of SWCNT outside the size-dependent region is about 480 kJ mol−1, which can be used for thermochemical calculations