Odd Pair Research Articles

Spin orbit scattering effect on long-range odd frequency triplet pairing in ferromagnet/superconductor bilayers

A formulation of triplet proximity effect in a ferromagnet/superconductor bilayer based on the de Gennes correlation function method is presented by extending the Takahashi–Tachiki theory. The inhomogeneous in-plane spiral magnetic order is employed in this approach the superconducting order parameter is a conventional spin singlet s-wave pairing, and the induced triplet pair amplitude arises as a result of the broken time-reversal invariance due to the presence of the rotating exchange field. A new type of triplet condensate still possesses the s-wave state but the symmetry requires an odd frequency parity. We find that the inhomogeneous exchange interaction leads to the appearance of the long-range odd frequency triplet pair amplitude, and the inclusion of the spin orbit scattering affects both short-range and long-range triplet components. The superconducting critical temperature of the diffusive ferromagnet/superconductor sandwiches is determined from the secular equation of the linearized gap equation in order to investigate the behavior of the induced triplet pairing. It is found that the induced long-range triplet component exists which arises from the modulation of the in-plane pair amplitudes in the transverse direction. Moreover, the possibility of the cryptoferromagnetic state is demonstrated in favor of superconductivity and this may explain a possible origin of the magnetically dead layer.

ODD FREQUENCY TRIPLET PAIRING COMPONENTS IN F/S/F TRILAYERS

We calculate the singlet and triplet pairing components of F/S/F trilayers by solving the Usadel equation in the dirty limit. Here, S is a conventional singlet s-wave superconductor like Nb and F is a ferromagnet like CoFe . A particular focus is on the odd frequency triplet pairing components which have a long length scale in F region unlike the singlet pairing component. The triplet components in F/S/F are induced by the broken time reversal symmetry and the proximity effects. The cases of parallel and perpendicular orientations of the two F's are calculated and discussed for the fingerprint of the odd frequency triplet pairing components.

Anomalous Josephson current by odd frequency Cooper pairs

The Josephson effect in superconductor/diffusive normal metal/superconductor junctions is studied theoretically, where the p-wave pairing symmetry is assumed in superconductors. The amplitudes of the Josephson current become much larger than those in the s-wave junctions because of a cooperative effect between the midgap Andreev resonant states and the proximity effect. We show that the Josephson current is carried by the odd-frequency Cooper pairs in diffusive metals.

Optimal Positions of Twists in Global On-Chip Differential Interconnects

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Crosstalk limits the achievable data rate of global on-chip interconnects on large CMOS ICs. This is especially the case, if low-swing signaling is used to reduce power consumption. Differential interconnects provide a solution for most crosstalk and noise sources, but not for neighbor-to-neighbor crosstalk in a data bus. This neighbor-to-neighbor crosstalk can be reduced with twists in the differential interconnect pairs. To reduce via resistance and metal layer use, we use as few twists as possible by placing only one twist in every even interconnect pair and only two twists in every odd interconnect pair. Analysis shows that there are optimal positions for the twists, which depend on the termination impedances of the interconnects. Theory and measurements on a 10-mm-long bus in 0.13-<formula formulatype="inline"><tex>$\mu$</tex> </formula>m CMOS show that only one twist at 50% of the even interconnect pairs, two twists at 30% and 70% of the odd interconnect pairs, and both a low-ohmic source and a low-ohmic load impedance are very effective in mitigating the crosstalk. </para>

Some nonclassical properties of a finite dimensional even and odd pair coherent state

The exponential form of even and odd pair coherent state (EOPCS) is constructed. The EOPCS is generalized to a finite dimensional EOPCS in the Hilbert space, and then its orthonormalized property, completeness relations and some noncalssical properties are discussed. It is shown that the finite dimensional EOPCS has normalized and completeness relations, but not orthogonal relations. By virtue of the numerical computation method, we find that, for any value of q, in different ranges of the parameter |ξ| the 5-dimensional EOPCS for the modes 1 and 2 exhibit anti-bunching effect and the photons between the two modes are always correlated. The different peak structures of the phase probability distributions for the 7-dimensional EOPCS show remarkably different quantum interference properties.

Relativistic mean-field study for Zn isotopes

The ground-state properties of Zn isotopes have been investigated using the deformed relativistic mean-field (RMF) theory with the NL-SH and TM1 forces. The π-meson and the spatial component of the ω-meson are taken into account. Shell effects in nuclear sizes and neutron skins are well described. Strong deformations are found for most of Zn isotopes. The shape coexistence of prolate-oblate types exists for a high portion of Zn isotopes. The occurrence of the superdeformed minimum in even isotopes is discussed. The π-meson contribution in ground-state properties of odd Zn isotopes is very limited, whereas the spatial component of the ω-meson that couples to the nonzero vector current in deformed odd nuclei gives rise to the degeneracy breaking of the level with opposite spin projections, playing the role of anti-pairing. The anti-pairing role in odd nuclei and pairing correlations with the Bardeen-Cooper-Schrieffer description in even nuclei are important to give the odd-even difference in charge radii, the prediction of the proton drip line, and possible abundance of the halo structure for neutron-rich isotopes.

"Pardon me, but your teeth are in my neck": Giambattista Marino, Claudio Monteverdi, and the bacio mordace

Claudio Monteverdi's "Eccomi pronta ai baci" presents an odd pairing of a first-person female voice with a three-voice low male ensemble; in addition, the text, by Giambattista Marino, deals with the subject of the "bacio mordace" [biting kiss], and the female speaker invites her lover to kiss her but warns him against biting her. He of course betrays her, and the poem closes with her outraged complaint and vow never to kiss him again. The combination of text, singing voices, and expressive qualities invoked in the setting suggests that Monteverdi went beyond the conceit of Marino's madrigal in exaggerating the comic and parodistic (in the non-musicological sense of the word) aspects of the situation. In this essay, I explore the background of the kiss imagery, focusing specifically on the "bacio mordace" as an expression of "lover's furor" in Classical and Renaissance sources. I then relate the particular conceit of Marino's poem to Emanuele Tesauro's analysis of the dynamics of literary comedy: the device of decettione [deception or reversal] as part of the ridicolo [comedy] and its attendant burle [pranks]. Finally, I offer a reading of Monteverdi's madrigal in terms of Tesauro's definitions, in which I argue that the setting interjects an extra level of interpretation between the poet and the audience. This musical "filter" introduces new ambiguity into the poem's already equivocal situation, expanding its comic aspects.

Using Literature to Teach Factorials

AT ONE TIME, NOT SO LONG AGO, we thought that we were a very odd pair. Although we were faculty members in middle school education at the same university, one of us was a reading educator and the other, a mathematics educator. What could we possibly have had in common? What could we talk about? And how could we talk about it to each other? We did not have the same professional backgrounds, and we surely did not speak the same language! Many of our colleagues just shook their heads and said that our collaboration would never work.

Magnetism and superconductivity in UT2Al3 (T=Pd, Ni) and UGe2

We review magnetic and superconducting properties of UT2Al3 (T=Pd, Ni) and UGe2 together with URu2Si2. For UPd2Al3, we have suggested that the superconducting attractive paring interaction is mediated by magnetic excitons. Knight shift measurements of UNi2Al3 show an odd parity pairing in contrast to an even parity formation in UPd2Al3. The ac magnetic susceptibility measurements of UGe2 indicate that the volume fraction of superconductivity grows with increasing pressure, suggesting inhomogeneous coexistence of superconductivity and ferromagnetism. Recent dc magnetization measurements on UGe2 exhibit a step like hysteresis loop at low temperatures. An analysis of the data suggests that a magnetic domain size is smaller than a superconducting coherence length. Finally, we report the observation of an anomaly appearing in the thermal expansion of URu2Si2 under high pressures, which can be ascribed to the phase transition between a hidden and antiferromagnetic order.

An Early Prediction of Maximum Sunspot Number in Solar Cycle 24

A non-linear coupling function between sunspot maxima and aa minima modulations has been found as a result of a wavelet analysis of geomagnetic index aa and Wolf sunspot number yearly means since 1844. It has been demonstrated that the increase of these modulations for the past 158 years has not been steady, instead, it has occurred in less than 30 years starting around 1923. Otherwise sunspot maxima have oscillated about a constant level of 90 and 141, prior to 1923 and after 1949, respectively. The relevance of these findings regarding the forecasting of solar activity is analyzed here. It is found that if sunspot cycle maxima were still oscillating around the 141 constant value, then the Gnevyshev–Ohl rule would be violated for two consecutive even–odd sunspot pairs (22–23 and 24–25) for the first time in 1700 years. Instead, we present evidence that solar activity is in a declining episode that started about 1993. A value for maximum sunspot number in solar cycle 24 (87.5±23.5) is estimated from our results.

Physics: Superconductor has odd electron pairing

Science NewsVolume 162, Issue 10 p. 158-158 Of Note Physics: Superconductor has odd electron pairing First published: 02 July 2009 https://doi.org/10.1002/scin.5591621019AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume162, Issue107 September 2002Pages 158-158 RelatedInformation

No odd pairs in minimal imperfect NP5 graphs

We prove that a minimal imperfect graph containing a vertex which is not on any induced P 5 has no odd pair.

African American workers and southern visitors at antebellum Saratoga Springs

The New York state resort of Saratoga Springs was virtually unique in the antebellum United States as a venue where slave owners, fleeing the pestilential diseases of the plantation, confronted free black workers, drawn by the easy availability of seasonal work. The interactions of this odd pairing, preserved in a few fragmentary texts, reveal a considerable degree of negotiation. Antebellum black workers at Saratoga often substituted everyday acts of rebellion for the perceived futility of open attacks on individuals or institutions of domination. If their self‐assertion did not translate into substantial economic or social gains, neither were they a particularly servile or degraded class. For Southerners, the spa was a liminal site filled with pleasurable and frightening possibilities in complete contrast to plantation life. Although planters often returned to the South confirmed in their racial and sectional fears, both groups found the resort a congenial place to experiment with new roles and new attitudes.

"L'Eglise Invisible" and "La Maison du Messie Charnel": The Saintly and Prophetic Voices of Les Grands cimetieres sous la lune

Drumont and Peguy In a characteristically audacious moment in Les Grands cimetieres sous lune (1938), Georges Bernanos imagines the funeral of his former political ally and maitre, (2) Charles Maurras, as grande manifestation d'union national--only to declare that n'y verra pas Drumont, ni Peguy, ni moi. (3) Writing in 1937, six years after his stormy break with Maurras, Bernanos makes his present allegiances clear. That he buries a living maitre while resuscitating two others, long dead, is not in itself surprising. Nor is it difficult to conceive either Edouard Drumont or Charles Peguy, as Bemanos imagines now one, now the other, snubbing Maurras along with him. It is their proximity that gives us pause. Only in Bernanos, and especially beginning with Les Grands cimetieres, do we find Drumont and Peguy hailed as partners in influence. (4) Bernanos, of course, looked well beyond their vehement opposition from either side of the Dreyfusard divide. He saw each as the author of an impassioned denunciation of mo dem politics and society: Peguy, disabused Socialist turned monarchist, lone defender of mystique over politique; (5) vieux Drumont--after the Affair, after the decline of La Libre parole--obscure prophet of La Fin d'un monde (1889). Even if we concentrate on whatever their destinies may have had in common, suspending other associations--Drumont's frenzied vilification of Jews in La France juive (1886), Peguy's near-sanctification of Bernard Lazare in Notre jeunesse (1910)--these two remain an odd pair of masters. We might ask how the grouping of Drumont and Peguy relates to the question of whether Les Grands cimetieres marks a change in Bernanos's thinking. For his part, he denies that he has changed (386). The pamphlet contains several indicators of change or evolution, the most obvious being political. Although Bernanos had already broken with Maurras and L'Action francaise when he and his family set out for Majorca in October 1934, it was very much expected that he would back the Christian side in the Spanish War. He did, in fact, support the Rebel cause during the early stages of the conflict. This early partisanship, however, was overshadowed by a subsequent condemnation of Franco and his fascist allies and of the role of the Catholic Church of Spain in the war. In contrast to the split from Maurras in 1932, which, though never to be reversed, had nonetheless been over a relatively trivial political issue, his position on the Spanish War signaled a major turning point. The former member of Les Camelots du roi a nd L'Action francaise would go on to oppose the Maurrasians over the signing of the Munich Pact (Scandale de verite, 1939) and throughout the war he would write on the side of the Resistance (Nous autres Francais 1939; Lettre aux Anglais, 1942). (6) Bernanos's acknowledgment of Drumont and Peguy together as maitres underscores what perhaps ought to be obvious--that his vision was only in the final instance political. Although he was constantly taking political stands and was long an active participant in political debates, he saw the world primarily through a metaphysical lens. At the same time, he never shied from confrontation with what Maurice de Gandillac, speaking about the evolution of thinking on the French Right, has called la realite politique: ... pour taus ceux qui ant pu subir 1'influence de Drumant, de Maurras et d'autres, ligne de clivage essentielle se situe au moment ou ces idees qui etaient, sinan de purs concepts, tout au mains des idees assez abstraites, sont passees dans in realite palitique. Mussolini avait ete relativement modere d' abord. Mais, avec guerre d'Espagne et guerre d'Abyssinie, le fascisme prenait un autre aspect. Et surtout avec Hitler. A ce moment-la il y a eu vraiment une coupure dans droite natianaliste francaise: certains ant subi fascination de Nuremberg, d'autres ont reagi a fois par patriotisme et par une certaine fidelite a des valeurs humanistes ou chretiennes. …

Asymmetric interdigitated metal-semiconductor-metal contacts for improved adaptive photoinduced-electromotive-force detectors

The use of interdigitated metal-semiconductor-metal contacts on semi-insulating GaAs enhances the responsivity of photoinduced-electromotive-force (photo-EMF) adaptive detectors by reducing the carrier transit time between electrical contacts. The unique polar character of the photo-EMF effect prevents the use of conventional interdigitated contact designs. For photo-EMF enhancement, the photoconductivity must be suppressed in every odd electrode pair. This is achieved through proton implantation to reduce the photocarrier lifetimes. The need to minimize the amount of area occupied by the back-action pairs while maintaining maximum collecting area between the active pairs is the source of the asymmetry. We present theoretical analysis of the scaling of the responsivity with the number of pairs. The theory is verified with experimental asymmetric interdigitated contact devices with 1, 2, 4, 8, 16, and 32 pairs of electrodes. The relative enhancement in responsivity is approximately equal to the number of pairs. The enhanced photo-EMF detectors have potential application to adaptive laser-based ultrasound detection.

Structure and properties of hydroxyl radical modified nucleic acid components: tautomerism and miscoding properties of 5-hydroxycytosine

The SCF ab initio quantum chemistry calculations of the 5-hydroxycytosine (5-OH-C) tautomer and its pairs with standard nucleic acid bases were performed. In the vapour state the keto–imino isomer is most stable among all possible H 1 tautomers. However, in the presence of a solvent field the most preferred is the keto–amino isomer. Thus, there is significant influence of the environment polarity on the tautomers succession. Such a behaviour is related to discrepancies in the dipole moments between the two most stable tautomers of 5-OH-C. The keto–imino form is less polar and has a dipole moment one order less then the keto–amino structure. The pairing potential of 5-OH–C was estimated on the basis of SCF calculations for the two most favourable tautomers. Both structures are able to form stable dimers with guanine, cytosine and to a lesser extent with thymine and adenine. The first does not lead to miscoding abilities. However, the formation of all other dimers may be responsible for observed in vivo miscoding properties of this DNA lesion. A comparison of the stabilisation energies to AT pair led to the conclusion that the resulting stabilisation energy is higher for pairs with guanine and cytosine but slightly lower for pairs with thymine and adenine. The presence of one of these odd pairs in the DNA may be responsible for CG⇒GC and CG⇒AT transversion or CG⇒TA transitions. These facts are in good agreement with in vivo and in vitro experimental observations. In the light of our results the source of such mutations may be related not only to the miscoding potential of dominant tautomer, but also to other, less stable tautomers of 5-OH–C.

P4-domination in minimal imperfect graphs

Numerous studies concerning the number and disposition of chordless paths on four vertices in graphs proved that there is a strong relation between these paths and the perfectness of graphs. In this paper, we further investigate this relation by introducing the notion of P 4-domination and formulating two conjectures, which are used both to find an equivalent version of the odd pair conjecture and to frame it. In the last section, we prove some particular cases of these conjectures.

Even and odd pairs in comparability and in P4-comparability graphs

We characterize even and odd pairs in comparability and in P 4-comparability graphs. The characterizations lead to simple algorithms for deciding whether a given pair of vertices forms an even or odd pair in these classes of graphs. The complexities of the proposed algorithms are O( n + m) for comparability graphs and O( n 2 m) for P 4-comparability graphs. The former represents an improvement over a recent algorithm of complexity O( nm).

Excitation of Oscillations - An Update of Bison Data

BiSON is a 6-station, world-wide network of instruments which observe low-degree solar oscillations.Theory (Goldreich &amp; Keeley, 1977) predicts that the probability distribution of the mode powers is expected to follow negative exponential statistics under the condition that the interval of time for which the modes are averaged is less than the lifetime of the mode. Simulations (Chaplin et al, 1997) confirm this. The first publication of such an analysis for real data (Elsworth et al., 1995) showed that the oscillations largely follow the predictions with a small excess of the very largest power in the modes. In this paper we extend the previous observations of BiSON data to 80 months of data taken during the declining phase of the solar cycle. The data span the period January 1990 to August 1996. The data have been analysed using Fourier transforms each about 1/2 day in length. The minimum data fill accepted in any one period was 0.7 (Elsworth et al, 1995). Below this fill the data were discarded. The resolution of such short transforms is insufficient to distinguish between the components of the even and odd mode pairs. The mode powers are calculated for mode pairs ℓ = 0 &amp; 2 and ℓ=1&amp;3.Comparison with theoretical predictions show that, as seen previously, there is still an excess of very high excitations which can be seen throughout the 80 months.

Path parity and perfection

Two nonadjacent vertices x and y in a graph G form an even pair if every induced path between them has an even number of edges. For a given pair { x, y} in a graph G, we denote by G xy the graph obtained from G by contracting x and y. In 1982, Fonlupt and Uhry proved that if G is perfect then so is G xy . In 1987, Meyniel used this fact to prove that no minimal imperfect graph contains an even pair. In the last eight years, even pairs have become an important tool for proving that certain classes of graphs are perfect and for designing optimization algorithms on special classes of perfect graphs. This paper surveys results of these types. It also discusses numerous related concepts including odd pairs.