{"title":"The magnetic properties of the Sherrington-Kirkpatrick model for spin glasses","authors":"G. Parisi","doi":"10.1080/13642818008245416","DOIUrl":"https://doi.org/10.1080/13642818008245416","url":null,"abstract":"Abstract We have studied the magnetic properties of the Sherrington-Kirkpatrick model for spin glasses by performing Monte Carlo simulations for 200 spins. Excellent agreement is found with the theoretical predictions of the new version of the replica theory.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78998424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"3d transition metal intercalates of the niobium and trantalum dichalcogenides","authors":"S. Parkin, A. Beal","doi":"10.1080/01418638008224031","DOIUrl":"https://doi.org/10.1080/01418638008224031","url":null,"abstract":"Abstract Optical reflectivity spectra of the first-row transition metal intercalation complexes, M1/3NbS2 and M1/3TaS2 (M = V, Cr, Mn, Fe, Co, Ni), Mn1/4 TaS2 and Fe1/4 NbSe2 have been measured at room temperature and compared with those for the host compounds, 2H NbS2, 2H TaS2 and 2H NbSe2. It is found that a simple rigid-band model is inconsistent with the data and that it is necessary to include both broadening of the valence and the lowest conduction band through increased interlayer interactions and broadening of the 3d energy levels on the intercalate ions through interaction with the Nb or Ta d-band conduction electrons. Quantitative analysis of the free-carrier reflectivity edge is performed by fitting to a simple Drude model from which the free-carrier effective mass and scattering time can be deduced.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91329272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Inada, A. Thamizhavel, H. Yamagami, T. Takeuchi, Y. Sawai, S. Ikeda, H. Shishido, T. Okubo, M. Yamada, K. Sugiyama, Noriko Nakamura, T. Yamamoto, K. Kindo, T. Ebihara, A. Galatanu, E. Yamamoto, R. Settai, Y. Ōnuki
{"title":"An unusual hollow cylindrical Fermi surface of a quasi-two-dimensional compound CeAgSb2","authors":"Y. Inada, A. Thamizhavel, H. Yamagami, T. Takeuchi, Y. Sawai, S. Ikeda, H. Shishido, T. Okubo, M. Yamada, K. Sugiyama, Noriko Nakamura, T. Yamamoto, K. Kindo, T. Ebihara, A. Galatanu, E. Yamamoto, R. Settai, Y. Ōnuki","doi":"10.1080/13642810208222948","DOIUrl":"https://doi.org/10.1080/13642810208222948","url":null,"abstract":"Abstract We have carried out the de Haas-van Alphen (dHvA) experiment, together with electrical resistivity, magnetic susceptibility, magnetization and specific heat experiments on a high-quality single-crystal CeAgSb2, which has a small net ferromagnetic moment of 0.4 μB per Ce atom. The bulk magnetic properties are well explained by the crystalline electric field scheme. On the other hand, large dHvA frequencies of 108 Oe, which correspond to cylindrical Fermi surfaces, were detected by the dHvA measurement for the magnetic field along the tetragonal [001] direction, indicating the quasi-two-dimensional electronic structure. The dHvA branches of CeAgSb2 are highly different from those with small dHvA frequencies of 107 Oe for the reference compounds LaAgSb2 and YAgSb2 which exhibit a semimetallic character. The dHvA results have been compared with the results of the energy band calculations. It was concluded that the 4f electron is mainly localized and that the Fermi surface of CeAgSb2 is similar to that of LaAgSb2, but it is slightly enlarged so as to form the large orbits along a hollow cylindrical Fermi surface.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"72 1","pages":"1867 - 1892"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74022298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A new hypothesis about the mechanism of magnetic-domain formation","authors":"F. Branda, G. Luciani, A. Costantini","doi":"10.1080/13642810208222947","DOIUrl":"https://doi.org/10.1080/13642810208222947","url":null,"abstract":"Abstract This paper proposes a mechanism of formation of the magnetic domains on cooling a ferromagnetic material from a higher temperature than the Curie temperature. It is derived from the well-known theory of crystallization in an amorphous material through a two-step mechanism of nucleation and crystal growth. Following this approach it is shown that the domain structure should depend on the free-energy change ΔG per mole of magnetic moment aligning in the same direction. A method to avoid calculation of ΔG is shown. This approach was successfully applied to explain the differences between the domain structures of the annealed and the as-quenched samples of the amorphous alloy Fe62.5Co6Ni7.5Zr6Cu1Nb2B15. Moreover, it gives an explanation for recent findings on the magnetic microstructure of high-permeability materials.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"26 1","pages":"1859 - 1865"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86425149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xin Zhang, J. Liao, Peijun Li, Z. Yin, Xiao-Xu Wu, X. Zong
{"title":"The origin of radiation instability in yttrium-ion-doped lead tungstate crystals","authors":"Xin Zhang, J. Liao, Peijun Li, Z. Yin, Xiao-Xu Wu, X. Zong","doi":"10.1080/13642810208222946","DOIUrl":"https://doi.org/10.1080/13642810208222946","url":null,"abstract":"Abstract Some Y3+-doped PbWO4 (PWO:Y3+) crystals grown by the modified Bridgman method showed exceptional behaviours, namely the increase in the light yield after low-dose-rate irradiation and also the improvement in the optical transmission at around 430 nm. In this paper, we studied the influences of high-temperature annealing in an oxygen-rich atmosphere on the stability of scintillation properties and radiation hardness of PWO: Y3+. The results show that annealing in oxygen enhances the absorption band at around 430 nm and makes optical transmission unstable at this wavelength after irradiation. After high-temperature annealing, the radiation-induced absorption coefficient is also negative around 430 nm. The 430 nm absorption band introduced by high-temperature annealing in oxygen has the same characteristics as the pre-existing bands in as-grown PWO: Y3+ crystals. So it decreases the stability of scintillation properties and radiation hardness of PWO: Y3+ crystals. The radiation instability relates to the formation of interstitial oxygen ions (Oi”) during high-temperature annealing. The results reveal that the oxygen-rich atmosphere during the crystal growth and annealing procedure is the origin of the exceptional irradiation behaviours in PWO: Y3+ crystals.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"91 1","pages":"1847 - 1857"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73911170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Invar effect in Pu-Ga alloys","authors":"A. Lawson, J. Roberts, B. Martinez, J. Richardson","doi":"10.1080/13642810208222945","DOIUrl":"https://doi.org/10.1080/13642810208222945","url":null,"abstract":"Abstract We show that the anomalous thermal expansion behaviour of Pu-Ga alloys can be explained by an Invar effect, which is modelled by assuming the thermal transfer of Pu atoms from a lower-energy higher-volume Δ1, state to a higher-energy lower-volume Δ2 state. The energy separation of these states is found to be 1400 K from a fit to the available neutron diffraction data on the lattice constants of Pu-Ga alloys. The Invar model enables a precise evaluation of the coefficient of thermal expansion and of the Grüneisen constant. The addition of Ga forces a stabilization of the Δ2 state and suppresses the negative thermal expansion.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"62 5","pages":"1837 - 1845"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72546068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Laviano, D. Botta, A. Chiodoni, R. Gerbaldo, G. Ghigo, L. Gozzelino, E. Mezzetti, S. Zannella
{"title":"In-plane field-effect correction in quantitative magneto-optical analysis","authors":"F. Laviano, D. Botta, A. Chiodoni, R. Gerbaldo, G. Ghigo, L. Gozzelino, E. Mezzetti, S. Zannella","doi":"10.1080/13642810208222944","DOIUrl":"https://doi.org/10.1080/13642810208222944","url":null,"abstract":"Abstract We present a detailed analysis of the calibration procedure to be performed in order to extract from magneto-optical images the local values of magnetic induction and electric current density on a plane over and inside the superconducting sample respectively. The interaction between the spontaneous magnetization of the indicator film and the full magnetic field distribution in the specimen region has been considered. In particular, the generally disregarded interaction of the indicator film with in-plane magnetic fields, that is with the component parallel to the indicator surface, is retained in the model. The current density distribution is obtained by the numerical inversion of the Biot-Savart law. In order to incorporate the in-plane field effect into the inversion scheme, we have constructed an iterative procedure which successfully takes into account the full magnetic induction field. A set of experimental data on a high-temperature superconducting YBa2Cu3O7-x film is presented to show the actual impact of the new analysis method, for what concerns both the local values of the magnetic induction and the electrical current density evaluation.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"15 1","pages":"1819 - 1835"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84037924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electronic band structure and the X-ray photoemission spectrum of UCu5In","authors":"G. Chełkowska, J. Morkowski, A. Szajek, R. Tro","doi":"10.1080/13642810208222949","DOIUrl":"https://doi.org/10.1080/13642810208222949","url":null,"abstract":"Abstract The family of compounds UCu5M (M ≡ Al, In or Sn) is characterized by the coexistence of magnetic order (antiferromagnetic for M ≡ Al and In; ferri-magnetic for M ≡ Sn) and Kondo lattice effects, by moderate electronic specific heat enhancement (γ/γ0 ≈ 8 for Al; γ/γ0 ≈ 11 for both In and Sn) and possibly a mixed-valence ground state. The electronic band structure was calculated by the tight-binding linear muffin-tin orbital method in the atomic sphere approximation. The electronic structure of UCu5In not unexpectedly shows marked similarities to the electronic structure of the other compounds of the family. The valence band, having a width of about 6eV, is due to prevalent contributions from the Cu 3d and U 5f electrons; the peak from the 5f electrons is situated just above the Fermi level. The X-ray photoemission spectra were taken in vacuum of 5 × 10−10 Torr from the sample surface prepared in situ. Satisfactory agreement between the measured spectrum and that obtained from the calculated electronic structure has been achieved.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"26 1","pages":"1893 - 1906"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88908143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Filamentary model of vibronic spectra of YBa2Cu3O6.95","authors":"J. C. Phillips","doi":"10.1080/13642810208223167","DOIUrl":"https://doi.org/10.1080/13642810208223167","url":null,"abstract":"Abstract Ellipsometric synchrotron spectroscopy of YBCO provides persuasive evidence supporting the Phillips-Jung (PJ) filamentary nanodomain model of the electronic structure of high-temperature superconductors (HTSCs). The PJ model is part of a universal off-lattice topological platform that explains the origin of the intermediate phase that is responsible for high-temperature superconductivity, the stiffness transition and reversibility window in network glasses, and the folding transitions of proteins. In HTSCs it is both more specific and more general than descriptions based on conventional collective modes related to charge-density waves.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"84 1","pages":"1703 - 1714"},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73124027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. X. Chen, J. Koike, T. Higuchi, S. Iwashita, M. Ishida, T. Shimoda
{"title":"Microstructure of epitaxial SrRuO3 films on Si(001) substrates","authors":"Y. X. Chen, J. Koike, T. Higuchi, S. Iwashita, M. Ishida, T. Shimoda","doi":"10.1080/13642810208223169","DOIUrl":"https://doi.org/10.1080/13642810208223169","url":null,"abstract":"Abstract The microstructure of pulsed-laser-deposited SrRuO3 films on Si(001) with SrO buffer layers has been studied by means of high-resolution electron microscopy and energy-dispersive X-ray spectroscopy. It was found that good epitaxial growths of the SrO buffer layers and the subsequent SrRuO3 films were achieved on the Si(001) substrates. Multiple domains were formed in the SrRuO3 films with domain boundaries nearly perpendicular to the interface between the SrRuO3 films and the SrO buffer layers. A high density of planar defects, such as twins, stacking faults and antiphase boundaries, were formed along the (022) lattice plane of the SrRuO3 films. Lattice strains in the constituting layers were investigated by means of fast Fourier transformation of local regions in the high-resolution images. It was found that, close to the interface between the SrRuO3 films and the SrO buffer layers, both the layers were elastically strained in the opposite sense. The structure of coherent twin boundary in the SrRuO3 films was determined using a computer-aided high-resolution image simulation method. The comparison between the simulated and the experimental images indicated that the Sr-O plane constituted the twin boundary.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":"33 1","pages":"1731 - 1748"},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74621627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}