Quantum Phases of Ultracold Bosonic Atoms in a One Dimensional Optical Superlattice

We analyze various quantum phases of ultracold bosonic atoms in a periodic one dimensional optical superlattice. Our studies have been performed using the finite size density matrix renormalization group (FS-DMRG) method in the framework of the Bose-Hubbard model. Calculations have been carried out for a wide range of densities and the energy shifts due to the superlattice potential. At commensurate fillings, we find the Mott insulator and the superfluid phases as well as Mott insulators induced by the superlattice. At a particular incommensurate density, the system is found to be in the superfluid phase coexisting with density oscillations for a certain range of parameters of the system.Comment: 7 pages, 11 figure

Cryptographic Key generation using Sclera and Finger Print: Proposed Method

Need for information security and privacy is increasing in recent times. Cryptography is intended to ensure the secrecy and authenticity of the message. The long cryptographic keys are very difficult to remember also protecting its confidentiality is one of the major issues to be deal with. These problems can be solved by integrating Biometrics with cryptography. Since biometric identifiers are unique to individuals, they are more reliable in verifying and identifying than knowledge based methods. Biometrics based authentication systems are progressively acquiring more attention in the field of research. Conventional techniques depend upon biometric features like face, fingerprint, iris, voice etc. In this paper we propose a method for cryptographic key generation fusing Finger print and Sclera

Hardcore bosons in a zig-zag optical superlattice

We study a system of hard-core bosons at half-filling in a one-dimensional optical superlattice. The bosons are allowed to hop to nearest and next-nearest neighbor sites producing a zig-zag geometry and we obtain the ground state phase diagram as a function of microscopic parameters using the finite-size density matrix renormalization group (FS-DMRG) method. Depending on the sign of the next-nearest neighbor hopping and the strength of the superlattice potential the system exhibits three different phases, namely the bond-order (BO) solid, the superlattice induced Mott insulator (SLMI) and the superfluid (SF) phase. When the signs of both hopping amplitudes are the same (the "unfrustrated" case), the system undergoes a transition from the SF to the SLMI at a non-zero value of the superlattice potential. On the other hand, when the two amplitudes differ in sign (the "frustrated" case), the SF is unstable to switching on a superlattice potential and also exists only up to a finite value of the next nearest neighbor hopping. This part of the phase diagram is dominated by the BO phase which breaks translation symmetry spontaneously even in the absence of the superlattice potential and can thus be characterized by a bond order parameter. The transition from BO to SLMI appears to be first order.Comment: 6 pages, 11 figure

Mean field analysis of quantum phase transitions in a periodic optical superlattice

In this paper we analyze the various phases exhibited by a system of ultracold bosons in a periodic optical superlattice using the mean field decoupling approximation. We investigate for a wide range of commensurate and incommensurate densities. We find the gapless superfluid phase, the gapped Mott insulator phase, and gapped insulator phases with distinct density wave orders.Comment: 6 pages, 7 figures, 4 table

Development of non-formaldehyde wrinkle resistant finish for cotton using carboxylic acids

475-481A study has been conducted to develop a wrinke resistant cotton fabric using three carboxylic acids combination along with initiator and catalyst, at various pH and concentration, and to determine the effects of treatment on wrinkle recovery angle, wrinkle recovery appearance rating, and carboxyl group content of the treated fabrics. The amount of carboxylic acids on the fabric is determined by % weight gain of treated samples, carboxyl ‘n’ group content, wrinkle recovery angle and wrinkle recovery appearance rating. Furthermore, FTIR spectroscopic analysis has been conducted to study the attachment of acid groups for reducing the available free OH groups on the cotton cellulosic chains. The results show significant wrinkle resistance of treated samples. In order to evaluate the wash durability of the finish applied, the treated sample is laundered for 20 cycles and it is found that the wrinkle recovery property significantly persist even after washing

Development of non-formaldehyde wrinkle resistant finish for cotton using carboxylic acids

A study has been conducted to develop a wrinke resistant cotton fabric using three carboxylic acids combination along with initiator and catalyst, at various pH and concentration, and to determine the effects of treatment on wrinkle recovery angle, wrinkle recovery appearance rating, and carboxyl group content of the treated fabrics. The amount of carboxylic acids on the fabric is determined by % weight gain of treated samples, carboxyl ‘n’ group content, wrinkle recovery angle and wrinkle recovery appearance rating. Furthermore, FTIR spectroscopic analysis has been conducted to study the attachment of acid groups for reducing the available free OH groups on the cotton cellulosic chains. The results show significant wrinkle resistance of treated samples. In order to evaluate the wash durability of the finish applied, the treated sample is laundered for 20 cycles and it is found that the wrinkle recovery property significantly persist even after washing

A first-principles thermodynamic approach to ordering in Ni-Mo alloys

There is a competition between several face centered cubic (FCC)-based ordered inter-metallic phases in Ni-Mo alloys containing 8-33 at% Mo. The transformation behavior of these alloys in terms of ordering instabilities has been studied. First-principles tight-binding-linear muffin-tin orbital (TB-LMTO) method coupled with augmented space recursion (ASR) in conjunction with orbital peeling (OP) technique has been employed to extract the concentration dependent effective pair interactions. Further, the mean-field statistical mechanics based static concentration wave (SCW) model has been used to determine the free energies of these ordered phases as functions of temperature, composition and order parameter. This ASR-OP-SCW approach, applied to Ni-Mo alloy system, gives the correct ground state stability sequence as observed experimentally. Furthermore, it has been shown that such an approach can be used to study the complex transformation behavior involving several competing superstructures as well as competing first order and second order ordering processes

Experimental study of geometric t-spanners : a running time comparison

The construction of t-spanners of a given point set has received a lot of attention, especially from a theoretical perspective. We experimentally study the performance of the most common construction algorithms for points in the Euclidean plane. In a previous paper [10] we considered the properties of the produced graphs from five common algorithms. We consider several additional algorithms and focus on the running times. This is the first time an extensive comparison has been made between the running times of construction algorithms of t-spanners

Whole-Genome Sequence of Drug-Resistant Mycobacterium tuberculosis Strain S7, Isolated from a Patient with Pulmonary Tuberculosis

Over the past decades, drug-resistant Mycobacterium tuberculosis strains have presented a significant challenge, with inadequate diagnosis of tuberculosis (TB) cases. Here, we report the draft whole-genome sequence of drug-resistant M. tuberculosis strain S7, which was isolated from a patient from Tripura, India, who was diagnosed with pulmonary TB