Unique Parity Research Articles

Absolutely secure distributed superdense coding: entanglement requirement for optimality

Superdense coding uses entanglement as a resource to communicate classical information efficiently through quantum channels. A superdense coding method is optimal when its capacity reaches Holevo bound. We show that for optimality, maximal entanglement is a necessity across the bipartition of Alice and Bob, but neither absolute nor genuine multipartite entanglement is required. Unlike the previous schemes, which can transmit either even or odd bits of information, we demonstrate a generalized dense coding protocol using the genuine multipartite entangled GHZ state to send arbitrary information bits. Expressed in the eigenbasis of different Pauli operators, GHZ state is characterized by a unique parity pattern which enables us to formulate a security checking technique to ensure absolute security of the protocol. We show this method is better applicable in a scenario, where the initial information is distributed among spatially separated parties. Finally, optimizing the number of qubit(s) sent to Bob, we construct a distributed dense coding method, which completely depicts absolutely secure quantum communication between many to one party.

SS6: Online Short-Code RAID-6 Scaling by Optimizing New Disk Location and Data Migration

Abstract Thanks to excellent reliability, availability, flexibility and scalability, redundant arrays of independent (or inexpensive) disks (RAID) are widely deployed in large-scale data centers. RAID scaling effectively relieves the storage pressure of the data center and increases both the capacity and I/O parallelism of storage systems. To regain load balancing among all disks including old and new, some data usually are migrated from old disks to new disks. Owing to unique parity layouts of erasure codes, traditional scaling approaches may incur high migration overhead on RAID-6 scaling. This paper proposes an efficient approach based Short-Code for RAID-6 scaling. The approach exhibits three salient features: first, SS6 introduces $\tau $ to determine where new disks should be inserted. Second, SS6 minimizes migration overhead by delineating migration areas. Third, SS6 reduces the XOR calculation cost by optimizing parity update. The numerical results and experiment results demonstrate that (i) SS6 reduces the amount of data migration and improves the scaling performance compared with Round-Robin and Semi-RR under offline, (ii) SS6 decreases the total scaling time against Round-Robin and Semi-RR under two real-world I/O workloads (iii) the user average response time of SS6 is better than the other two approaches during scaling and after scaling.

Discotic liquid crystals of transition metal complexes 59 : Parity effect of the number of d-electrons on the columnar mesomorphism and homeotropic alignment of 1,4-diazatriphenylenocyaninato metal(II) complexes

Twenty super-discotic liquid crystals based on a largely expanded [Formula: see text]-conjugated macrocycle of 1,4-diazatriphenylenocyaninato metal(II) complex, (abbreviated as (C[Formula: see text]O)[Formula: see text]TzM: M = Co(1), Ni(2), Cu(3), Zn(4); [Formula: see text] = 8(a), 10(b), 12(c), 14(d), 16(e)) were synthesized in order to investigate their mesomorphism and homeotropic alignment properties by using polarization microscopic observations, differential calorimetry, thermogravimetry, and temperature-variable X-ray diffraction. As a result, the (C[Formula: see text]O)[Formula: see text]TzCo and (C[Formula: see text]O)[Formula: see text]TzCu complexes with an odd number of [Formula: see text]-electrons in the central metal ions showed a tetragonal columnar (Col[Formula: see text] mesophase for [Formula: see text] = 8[Formula: see text]14, which exhibit spontaneous homeotropic alignment for a very wide temperature range from rt to the decomposition temperature at around 340[Formula: see text]C. On the other hand, the (C[Formula: see text]O)[Formula: see text]TzNi and (C[Formula: see text]O)[Formula: see text]TzZn complexes with an even number of [Formula: see text]-electrons in the central metal ions showed a rectangular columnar (Col[Formula: see text](P21/a[Formula: see text] mesophase for [Formula: see text] = 8[Formula: see text]16, which did not exhibit homeotropic alignment. As far as is known, such a unique parity effect of the number of [Formula: see text]-electrons on mesomorphism accompanied by homeotropic alignment has never been reported to date.

Quasiparticle structure of superheavy nuclei in α-decay chains of 285Fl and 291,293Lv

Two mean-field potentials, Woods-Saxon and Skyrme based potentials, are used to calculate the energies of low-lying one-quasiparticle states. The spectra of the low-lying states and the α-decay spectra of nuclei belonging to the α-decay chains of 285Fl and 291,293Lv are calculated and compared with the available experimental data. Dependence of the splitting of the pseudospin doublets and of the energies of the unique parity neutron one-quasiparticle states on the mean field potential are discussed. As shown, the α-decay spectra could be different in the α-decay chain and at the direct production of the nucleus in a fusion reaction.

Structure evolution and phase transition in odd-mass nuclei

The evolution of level structures due to the unique parity orbitals ${g}_{9/2}$, ${h}_{11/2}$, and ${i}_{13/2}$ in odd-mass nuclei from Zn to Am is studied within a unified framework, by correlations between ratios of excitation energies in both odd-mass nuclei and their even-even core nuclei. These plots reveal regularities that can be understood in terms of the particle-plus-rotor model, as evolutions along its three limiting coupling schemes: weak coupling, decoupling, and strong coupling, and transitions between them. Peculiar transitions between the decoupling and strong coupling schemes are found in both ${i}_{13/2}$ structures of neutron-odd nuclei and ${h}_{11/2}$ structures of proton-odd nuclei, at neutron numbers around 90 and 70, respectively. These are correlated with the critical shape phase transitions from vibrator to rotor from the even-even nuclei in the same regions and are characterized as critical phase transitions too. This behavior is corroborated with a nonmonotonic behavior of the differential variation of the two-neutron separation energies in the same nuclear regions.

Dynamic erasure coding decision for modern block-oriented distributed storage systems

Modern block-oriented distributed storage systems like Hadoop distributed file system have proliferated in this era of big data and cloud computing. These systems feature block-level replication in which their files are partitioned into equal-sized blocks and multiple copies for each block are then arbitrarily distributed across nodes for fault tolerance and data availability. However, many storage volumes are just wasted only for keeping block copies whose data may not be accessed frequently in the strategy. Therefore, distributed storage systems begin to adopt erasure codes. However, classical parity encoding scheme are hard to be directly applied to the distributed storage systems since block copies are arbitrarily placed across nodes in the systems. We present a novel technique, called DynaEC, to address the issues in modern block-oriented distributed storage systems. DynaEC provides a unique parity encoding algorithm that encodes data blocks arbitrarily distributed across machines to parities and then places the parities guaranteeing fault tolerance. Parity encoding in DynaEC is performed without any change of the original block placement policy in Hadoop distributed file system. This makes DynaEC work seamlessly with Hadoop distributed file system. Finally, during the encoding procedure each data node encodes each own data blocks, not requiring any information about other blocks located in other data nodes. As such, the encoding procedure in DynaEC is fully performed in parallel without any synchronization issue. With extensive experiments, we show that DynaEC saves storage volumes up to the theoretical limit while outperforming previous approaches by multiple orders of magnitude.

Quasiparticle structure of superheavy nuclei along theα-decay chain of115288

Background: Recent experiments on $\ensuremath{\alpha}$-decay of odd-odd superheavy nuclei give important information on the structure of the low-lying states of these nuclei. For this reason, it is interesting to calculate the excitation spectra of superheavy nuclei in the framework of different approaches and compare the results with the experimental data.Purpose: To calculate the excitation energies of the two-quasiparticle states of nuclei belonging to the $\ensuremath{\alpha}$-decay chain of $^{288}115$ nucleus.Method: Two different single-particle potentials, modified two-center and Skyrme-based potentials, are used to calculate the energies of two-quasiparticle states.Results: The spectra of the low-lying states are calculated. An evolution of the splitting of the pseudospin doublets and an evolution of the energies of the unique parity single-particle states with the nuclear mass number are investigated. The $\ensuremath{\alpha}$-decay spectra of nuclei belonging to the $\ensuremath{\alpha}$-decay chain of $^{288}115$ are obtained and compared with the experimental data. A possibility of the $E1$ transitions in $^{276}\mathrm{Mt}$ following $\ensuremath{\alpha}$ decay of $^{288}115$ is considered.Conclusion: The $E1$ transitions in $^{276}\mathrm{Mt}$ might be related to the transitions $n9/2[604]\ensuremath{\rightarrow}n11/2[725],\phantom{\rule{0.16em}{0ex}}n11/2[725]\ensuremath{\rightarrow}n9/2[615]$, and $p9/2[505]\ensuremath{\rightarrow}p11/2[615]$. Besides the $E1$ transitions, the strong $M1$ and $M2$ transitions are expected in $^{276}\mathrm{Mt}$.

Problems of Cosmopolitanism and Alternativeness in the History of Central Asia

We residents of Samarkand and Bukhara, throughout history aimed to accumulate traditions of challenging the established (often elitist) limits of local culture, economics and history. The cities communities were under constant pressure of the dichotomy between the notions of nomadism and sedentism, Turkic and Persian speakers. Many community-based units of Samarkand had their own commercial, socio-cultural and educational networks that preserved alternativeness within the life cycle, which balanced between universality and particularism. These lands were dominated by a unique parity, based on Sufi ethics, which designed not syncretic cosmopolitism, but rather introduced the recognition of alternativeness that took into account both similar and diverse waves of ideas. Based on this vision, the author aims to diminish Kantian cosmopolitanism to a level of Euro-American and illustrate the view of cosmopolitanism through a dialogic platform, precisely including its links with the Central Asian versions. Moreover, one cannot identify local cosmopolitanism with the ideas of European Enlightenment, namely individualism and universalism on a global scale. Due to the alternativeness and cosmopolitanism, as well as lack of radical individualism within the local communities, there was no monocultural view on life, since both science and morality (religion, culture, and community) were mutually essential. Nonetheless, present proves that these fields remain their equal vitality to an individual who is capable of simultaneously possessing knowledge about the reality and receiving satisfaction from the reality. This constant motion based on reciprocation was maintained in the ancient culture of Samarkand by two factors: cosmopolitanism and alternativeness.

Relativistic dynamics compels a thermalized fermi gas to a unique intrinsic parity eigenstate

The Dirac equation describes the dynamics of a relativistic spin-1/2 particle regarding its spatial motion and intrinsic degrees of freedom. Here we adopt the point of view that the spinors describe the state of a massive particle carrying two qubits of information: helicity and intrinsic parity. We show that the density matrix for a gas of free fermions, in thermal equilibrium, correlates helicity and intrinsic parity. Our results introduce the basic elements for discussing the spin-parity correlation for a Fermi gas: (1) at the ultra-relativistic domains, when the temperature is quite high, , the fermions have no definite intrinsic parity (50% : 50%), which is maximally correlated with the helicity; (2) at very low temperature, K, a unique parity dominates (conventionally chosen positive), by to 1, while the helicity goes into a mixed state for spin up and down, and the quantum correlation decoheres. For the antifermions we get the opposite behavior. In the framework of quantum information, our result could be considered as a plausible explanation of why we accept, as a fact (consistent with the experimental observation), that fermions (and antifermions), in our present epoch of a cool universe, have a unique intrinsic parity. The framework for constructing spin-parity entangled states is established.

OPPORTUNITIES FOR COLLECTIVE MODEL AND CHIRALITY STUDIES AT TRIUMF

First predictions for a specific case of the particle-hole-core coupling model which takes advantage of symmetries of a triaxial rotor with γ = 90° are reviewed. Results of the model calculations point towards existence of stable chiral geometry in specific configurations involving high-j orbitals. Next, experimental information on doublet bands built on unique parity, πh11/2νh11/2 intruder states in odd-odd 134 Pr is discussed; in particular observed disagreements between electromagnetic transitions within the doublet structures which is pointed out as inconsistent with the simplest models. Finally, the unique experimental infrastructure developed at the Tri-University Meson Facility (TRIUMF) Canada's National Laboratory for Particle and Nuclear Physics is presented including a range of isotopes in the mass 130 region that are accessible as beams and which can possibly yield significant new information in investigations of nuclear chirality.

Parity and disparity subgraphs

A parity subgraph of a graph is a spanning subgraph such that the degrees of each vertex have the same parity in both the subgraph and the original graph. Known results include that every graph has an odd number of minimal parity subgraphs. Define a disparity subgraph to be a spanning subgraph such that each vertex has degrees of opposite parities in the subgraph and the original graph. (Only graphs with all even-order components can have disparity subgraphs). Every even-order spanning tree contains both a unique parity subgraph and a unique disparity subgraph. Moreover, every minimal disparity subgraph is shown to be paired by sharing a spanning tree with an odd number of minimal parity subgraphs, and every minimal parity subgraph is similarly paired with either one or an even number of minimal disparity subgraphs.

Microscopic calculations for upper-fp,g9/2 shell nuclei: Ge & Se

Shell-model calculations for isotopes of Ge and Se are reported where valence nucleons beyond the N = 28 = Z core occupy levels of the normal parity upper-fp shell (f5/2,p3/2,p1/2) and the unique parity g9/2 intruder configuration. Results are given for realistic interactions of the Kuo-Brown-3 type with various model space truncations that key in on the number of nucleon pairs allowed to occupy the intruder level. Electromagnetic (E2 & M1) rates as well as decay probabilities are calculated, some of which are key in determining the structure of “waiting point” nuclei that regulate certain nucleo-astrosynthesis processes. The role of the intruder level, which is treated on an equal footing with the normal parity levels, is shown to be important for reproducing structural details. The levels of the upper-fp shell are handled within the framework of a normal ls-coupled basis as well as its pseudo-SU(3) counterpart, and respectively, the g9/2 as a single level and as a member for the complete gds shell. The second of these two approaches, namely, the SU(3) picture, allows one to better probe the effect of deformation.

Global anharmonic vibrator behaviour of one-quasiparticle structures in odd- A nuclei and the IBFA model

We show that the anharmonic vibrator behaviour recently discovered both for the yrast states of the collective non-rotational even-even nuclei and for the unique parity orbital structures in their odd- A neighbours is also obeyed by all the other one-quasiparticle structures in the odd-mass nuclei. One-shell Interacting Boson-Fermion Model calculations with parameters randomly distributed within the model parameter space reproduce in a natural way the observed empirical anharmonic vibrator behaviour.

Global correlations of unique parity structures in odd-A nuclei

All known unique parity structures in precollective odd-A nuclei (having cores with E(4 1 +) E(2 1 +) < 2.0 ) are shown to behave similarly to the yrast quasibands in the neighboring even-even nuclei. This is interpreted in terms of a pair addition mode. With previous results on collective nuclei, this gives a tripartite classification of the evolution of the unique parity quasibands in odd-A nuclei. A simple index for signature splitting is also developed which avoids the need for complex analysis of Routhian structures.

Global phenomenology of B(E2) values in unique parity quasibands of odd- A nuclei

We have studied the evolution of the values in all the unique parity quasibands in odd-A nuclei, determined by the orbitals with j = 9/2, 11/2 and 13/2 ( and ). It is found that most of the known values, when normalized by the mass number and represented against , follow a compact, universal envelope, well represented by a simple function. This universal correlation is similar in spirit to those existing for the values in the even - even nuclei. It also highlights deviating cases, which indicate interesting phenomena, other than simple quadrupole deformation. The B(E2) values in the odd-A nuclei are, on average, higher than those in even - even nuclei.

Evidence of unique-parity band structure in neutron-rich odd-A Ru isotopes.

With prompt \ensuremath{\gamma}-ray and x-ray spectroscopy on fission fragments, several new transitions in $^{109,111}\mathrm{Ru}$ have been identified. Angular correlation analysis of several of the new transitions yield evidence of a stretched E2 band structure. Qualitative Nilsson model arguments, systematics, and triaxial rotor+particle calculations support our hypothesis that the observed band is built on the unique parity \ensuremath{\nu}${\mathit{h}}_{11/2}$ orbital.

On the treatment of intruder levels in strongly deformed nuclei in the framework of the SU(3) shell model

Abstract A model system which mimics the shell-model dynamics of strongly deformed nuclei is constructed in order to study the role of particles in the unique parity orbitals of heavy deformed nuclei and to test the validity and applicability of some commonly used truncation procedures. Working in a truncation-free environment and including quadrupole-quadrupole, spin-orbit, orbit-orbit, and pairing forces, we find that for standard nuclear systems the correlations generated among particles in the unique parity space and by the interaction of nucleons in the normal parity orbitals with those in the unique parity orbitals play an important role in driving the many-particle system towards its maximum allowed deformation. The results suggest that nucleons in the unique parity levels contribute significantly to the overall collectivity of a nuclear system and should be taken into account explicitly whenever possible, or at least through renormalization procedures that can be justified in special cases, like for collective states below the backbending region.

Global systematics of unique parity quasibands in odd-A collective nuclei.

All known structures in the collective medium and heavy odd-A nuclei, based on the unique parity orbitals ${\mathit{g}}_{9/2}$, ${\mathit{h}}_{11/2}$, and ${\mathit{i}}_{13/2}$, are collected and correlations between the energies within both the favored and unfavored quasibands are analyzed. A first startling result is that irrespective of the nature of the odd particle and the shell model orbital, for most of the nondeformed nuclei the energies within these quasibands, show a universal behavior of an anharmonic vibrator with a constant anharmonicity, identical with that found for the even-even nuclei. Second, the rapid transition between the anharmonic vibrator and the rotor regimes, which takes place in the even-even nuclei, is accompanied, in the adjacent odd-A nuclei, by an equally rapid transition from the anharmonic vibrator to the strong coupling regime.

Transformation to pseudo-spin-symmetry of a deformed Nilsson hamiltonian

The explicit form of the unitary operator connecting the normal parity Nilsson states, of a shell N, with the full set of eigenstates of a pseudodeformed oscillator is given. It is shown that after the transformation pseudo-spin partners are nearly degenerate. The transformation differs from the one of the spherical case indicating a dissimilar definition of normal and unique parity spaces. The division of the shell model space into normal and unique as proposed in the asymptotic limit may be useful in applications to superdeformation phenomena.

Alignment effects in odd-mass Cs isotopes: Spectroscopy of 125Cs.

Several rotational bands have been populated in the Z=55 nucleus $^{125}\mathrm{Cs}$ using the fusion evaporation reaction $^{110}\mathrm{Pd}$${(}^{19}$F,4n), at a beam energy of 74 MeV. The resultant \ensuremath{\gamma} rays were detected using standard \ensuremath{\gamma}-ray spectroscopic techniques with an array of six Compton-suppressed Ge detectors and a fourteen-element bismuth-germanate ball. The low-lying yrast structure is found to be dominated by the unique parity \ensuremath{\pi}${\mathit{h}}_{11/2}$ orbital, manifest as a decoupled band with a large signature splitting. A crossing occurs in this band at \ensuremath{\Elzxh}${\mathrm{\ensuremath{\omega}}}_{\mathit{c}}$=0.42 MeV, which is interpreted as [\ensuremath{\nu}${\mathit{h}}_{11/2}$${]}^{2}$ pair alignment. In addition, a strongly coupled negative-parity structure with large B(M1)/B(E2) ratios is observed feeding both signatures of the \ensuremath{\pi}${\mathit{h}}_{11/2}$ band. Bands built on the normal-parity \ensuremath{\pi}${\mathit{g}}_{7/2}$ and \ensuremath{\pi}${\mathit{g}}_{9/2}^{\mathrm{\ensuremath{-}}1}$ orbitals have also been confirmed and extended. These structures are compared to cranked-shell-model calculations and the systematics of the region.