Blind encoding into qudits

We consider the problem of encoding classical information into unknown qudit states belonging to any basis, of a maximal set of mutually unbiased bases, by one party and then decoding by another party who has perfect knowledge of the basis. Working with qudits of prime dimensions, we point out a no-go theorem that forbids shift operations on arbitrary unknown states. We then provide the necessary conditions for reliable encoding/decoding.Comment: To appear in Physics Letters

Sb2Te3 crystal a potential absorber material for broadband photodetector: a first-principles study

Antimony telluride (Sb2Te3), a layered semiconductor material, is considered a promising absorbing material for a high-performance optoelectronic device within broadband wavelengths because of remarkable features like strong optical absorbance and the narrow direct band gap. In this work, based on the first-principles approach, we investigate in detail the structural, electronic and optical properties of the hexagonal Sb2Te3 compound. The structural and electronic properties were computed using the first-principles approach, treating exchange–correlation potential with generalized gradient approximation (GGA) within density functional theory (DFT). Furthermore, for accurate prediction of the band gap, we go beyond DFT and calculated band structure using GW correction. The optical properties, namely, imaginary and real parts of complex dielectric function, absorption coefficient, refractive index, reflectivity, extinction coefficient, electron energy loss function and optical conductivity are performed by quasi-particle many-body perturbation theory (MBPT) via Bethe-Salpeter equation (BSE). The computed structural parameters are in good agreement with available experimental data. The obtained quasi-particle (GW) correction band structure show the semiconducting character of Sb2Te3 material with a direct band gap Eg of 0.221 eV, in agreement with previously reported value (Eg = 0.210 eV) while the projected density of states indicates (PDOS) that the p-orbital of Sb and Te atoms are responsible for material properties near the Fermi level. To our knowledge, our first reported calculations of optical properties, with the inclusion of electron-hole effects are consistent with available experimental measurements. Consistencies of our findings with experimental data validate the effectiveness of electron-hole interaction for theoretical investigation of optical properties

Entropic bounds as uncertainty measure of unitary operators

We reformulate the notion of uncertainty of pairs of unitary operators within the context of guessing games and derive an entropic uncertainty relation for a pair of such operators. We show how distinguishable operators are compatible while maximal incompatibility of unitary operators can be connected to bases for some subspace of operators which are mutually unbiased

Gender Dependence in Mouth Opening Dimensions in Normal Adult Malaysians Population

While measurement of mouth opening is an important clinica examination in diagnosis and management of oral disease, data on non-Western populations are limited. This study was therefore conducted to determine the range of mouth opening in normal Malaysian male and female adults. A total of 34 dental students of Universiti Sains Malaysia (USM) were chosen randomly and their maximum mouth opening was measured after being asked to open their mouth sufficiently to accommodate three fingers. Measurement was performed from the edge of the upper incisor to the lower incisor using a caliper divider. The difference of median values between male (47.6 mm) and female (40.8 mm) were significant respectively (p<0.05). Thus the width of mouth opening in Malaysian student population is gender dependent although further study with a larger sample size and with other ethnic groups should be carried out, focusing on age

Electronic and optical properties of Bi2Se3 topological insulator: a promising absorbing layer for broadband photodetector

Bismuth selenide (Bi2Se3) is a van der Waals compound which has been excellently reported as thermoelectric material. Linear dispersion near Fermi energy level is an exciting feature to consider, a promising candidate for photonic device within broadband wavelengths. For this application, detailed knowledge of its structural, electronic and optical properties is very essential. The electronic properties were determined by density functional theory (DFT) calculations implemented in Quantum-Espresso simulation package which uses plane wave basis and pseudopotential for the core electrons. Optical properties are computed by solving Bethe-Salpeter equation of many-body perturbation theory (MBPT) as implemented in Yambo code. The band structure results show the semiconducting behaviour of Bi2Se3. Taken into account the effects of electron-hole interaction by solving Bethe-Salpeter equation, the calculated optical properties are in better agreement with available experimental results. The exciton energy shows that the title material can absorb light within infrared region

Linear acenes linked thiophene, electronic and chemical properties: Prospects for molecular organic electronic material

We report a theoretical study of linear acene (n=1 to 7) linked thiophene properties functionality. The total ground state and band gap energies, Coulomb potential and nuclear repulsion energy are calculated by DFT, MP2 at B3LYP exchange level of the theory and 6-311G* basis set. The results are in good agreement with the experimental and theoretical values. It is found that the total ground state energy of the system and band gap energy decreases with an increasing number of electrons in the rings. The addition of thiophene molecules tends to improve the electronic and chemical properties of the linear acenes, the material exhibit potential application in the organic molecular electronic material

First principles study of structural, electronic and optical properties of half-heusler alloys LIMGN, NaMGN and KMGN

In this study, we performed our calculations using the full-potential linearized-augmented plane wave (FP-LAPW) method as implemented in the WIEN2k code based on DFT. The generalized gradient functional with the Wu-Cohen (WC) parameterization was used to evaluate the structural, electronic, optical and thermoelectric properties of the materials under this study. We have calculated the structural parameters and our obtained results are in good agreement with available experimental and previous theory calculations. The density of states and band structure figures have been calculated and analyzed. The optical properties that covered by dielectric function, absorption coefficient, refractive index, extinction coefficient, reflectivity and energy-loss function have been calculated and analyzed in a range energy from 0eV to 30eV

Investigation of structural, electronic and thermoelectric properties of XCUOTE (X: BI, CE, LE) with GGA-WC exchange correlation functional

Linearized augmented plane wave plus local orbitals (LAPW + lo) method designed within density functional theory (DFT) has been used in this study to calculate the structural, electronic and thermoelectric properties of XCuOTe (X=Bi, Ce, La). Generalized gradient approximation, Wu-Cohen (GGA-WC) parameterized exchange correlation functional, was used. The structural and electronic calculations have a good agreement with previous study. For thermoelectric calculation, semi empirical Boltzmann approach implemented in BoltzTraP package was used to calculate Seebeck coefficient, electronic conductivity as well as thermal conductivity. By referring to previous studies, the results have good agreement with them. In addition, the Seebeck coefficient of these materials was calculated as a function of the chemical potential at temperatures 300K, 600K, and 900K. Our calculations highlight suitability of these materials for applications in thermoelectric devices

Association between TAS1R2 gene polymorphism (rs12033832) and sweet taste perception amongst Malay obese and non-obese subjects

Introduction: A growing evidence supported that variation of sweet taste perception, mediated by TAS1Rs gene variants could lead to excess sweetened food and beverages intake and also obesity. However, obesity development may also alter individuals' taste sensitivity and perception. Thus, it is best to further investigate whether or not the individuals' sweet taste sensitivity and acceptance are associated with variation in TAS1R2 gene and Body Mass Index (BMI) status. Methods: This comparison cross sectional study comprised of 88 obese and 92 non-obese subjects aged 20-45. All the subjects were genotyped for TAS1R2 gene variant at rs12033832 using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP). Suprathreshold sensitivity for sweet taste was assessed using general Labeled Magnitude Scales. Intensity rating and hedonic test were carried out on 2 food samples (tea drink and rose flavoured agar) to examine subject's intensity rating and liking at different sugar contents. Results: Our results showed that rs12033832 of TAS1R2 gene is associated with sweet taste perception among obese and non-obese subjects. No interaction effect between BMI status and TAS1R2 gene variant (rs12022832) was found on sweet taste measures. Overall, non-obese subjects with AA genotype on rs12033832 had the highest sweet taste sensitivity and dislike high sugar content products the most. The effect was reverse among the obese subjects with GG homozygous. Conclusion: These findings suggest that TAS1R2 gene variation plays an important role in sweet taste perception among individuals and may have nutritional implications and obesity. © 2020 UPM Press. All rights reserved