SVIBOR - Papers quoted in CC - project code: 1-03-054

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Papers quoted in Current Contents on project 1-03-054

Quoted papers: 65
Other papers: 51
Total: 116

Title: The Influence of Chemical Impurities and X-ray Induced Defects on the Single-Particle and Spin-Density Wave Conductivity in the Bechgaard Salts

Authors:: Tomić, Silvia (65594); Cooper, John Robert (7044); Kang, W.; Jerome, D.; Maki, K.

Journal: J.Phys.(France)
ISSN: 1155-4304
Volume: 1
Year: 1991
Pages: from 1603 to 1625
Number of references: 62
Language: engleski
Summary: We present some recent experimental and theoretical results onthe single particle and spin-density wave (SDW) conductivity inBechgaard salts (TMTSF)2NO3 and (TMTSF)2PF6. Particularemphasisis is paid to the clearest example (TMTSF)2PF6 for whichthere is experimental evidence, namely the absence of 2kF diffusescattering at low temperatures, for a pure SDW state below 12K. Atheoretical analysis starting from the anisotropic Hubbard modeland taking into account the influence of long range Coulombinteractions can account for many features of the experimentaldata. The magnitude and temperature dependence of the thresholdfield and to some extent the magnitude of the SDW conductivityare well accounted for by this theory. Comparison withexperimental data shows that for most batches of samples the SDWis weakly pinned to randomly distributed impurities of defects.Defects were then introduced in a controlled way by X-rayirradiation. This caused a substantial increase in thresholdfield and a changeover to the behaviour expected for a stronglypinned SDW.

Title: Temperature Dependence of the Hall Angle in Single Crystal YBa2(Cu1-xCox)3O7-d

Authors:: Carrington, A.; MacKenzie, A.P.; Lin, C.T.; Cooper, John Robert (7044)

Journal: Phys.Rev.Lett.
ISSN: 0031-9007
Volume: 69
Year: 1992
Pages: from 2855 to 2858
Number of references: 21
Language: engleski

Title: 12kBTc Optical Signature of Superconductivity in Single Domain Bi2Sr2CaCu2O8

Authors:: Romero, D.B.; Carr, G.L.; Tanner, D.B.; Forro, L. (114515); Mandrus, D.; Mihaly, L.; Williams, G.P.

Journal: Phys.Rev.B
ISSN: 0163-1829
Volume: 44
Year: 1991
Pages: from 2818 to 2821
Number of references: 22
Language: engleski

Title: Observation of the Conductivity Coherence Peak in Superconducting Bi2Sr2CaCu2O8 Single Crystals

Authors:: Holczer, K.; Forro, L. (114515); Mihaly, L.; Gruner, G.

Journal: Phys.Rev.Lett.
ISSN: 0031-9007
Volume: 67
Year: 1991
Pages: from 152 to 155
Number of references: 15
Language: engleski

Title: Quasiparticle Damping in Bi2Sr2CaCu2O8 and Bi2Sr2CuO6

Authors:: Romero, D.B.; Porter, C.D.; Tanner, D.B.; Forro, L. (114515); Mandrus, D.; Mihaly, L.; Carr, G.L.; Williams, G.P.

Journal: Phys.Rev.Lett.
ISSN: 0031-9007
Volume: 68
Year: 1992
Pages: from 1590 to 1593
Number of references: 20
Language: engleski

Title: Electrical Transport in the Organic Superconductor betha-(BEDT-TTF)2AuI2 : Influence of X-Ray Induced Defects on the Normal Phase and Superconducting Ground State

Authors:: Dolanski Babić, Sanja (188231); Biškup, Neven (179286); Tomić, Silvia (65594); Schweitzer, D.

Journal: Phys.Rev.B
ISSN: 0163-1829
Volume: 46
Year: 1992
Pages: from 11765 to 11772
Number of references: 31
Language: engleski
Summary: We have measured the in-plane and out-of-plane resistivities ofteh organic superconductor betha-(BEDT-TTF)2AuI2 with disorderintroduced by x-ray irradiation. For defect concentrations lessthan 0.15%/mole, Matthiessen's rule is obeyed at all temperaturesand a T2 term in the resistivity is found in the temperatureregion between 5 and 20K. The long-range superconducting order isdestroyed by 0.1%/mole and the transition is completely smearedout above 0.2%/mole of defects. The overall temperature behaviourof the resistivity is discussed and the possible importance ofthe electron-electron interaction and two-dimensionallocalization for the stabilization of the superconducting groundstate is emphasized.

Title: Defect-Concentration Dependence of the Spin-Density Wave Transport in the Organic Conductor (TMTSF)2PF6

Authors:: Kang, W.; Tomić, Silvia (65594); Jerome, D.

Journal: Phys.Rev.B
ISSN: 0163-1829
Volume: 43
Year: 1991
Pages: from 1264 to 1268
Number of references: 13
Language: engleski
Summary: We have studied the effects of chemical impurities and x-rayirradiation-induced defects on the electric-field-dependentconductivity in the spin-density wave (SDW) state of the organicconductor (TMTSF)2PF6. For a large number of nominally puresamples the temperature dependence of the threshold field agreeswith theoretical predictions that assume weak coupling betweenthe SDW and chemical impurities. For irradiated samples thethreshold field increases linearly with defect concentration andits temperature dependence corresponds to that expected in thestrong-coupling limit.

Title: Correlations between Bond Lengths, Tc and O Vibration Frequencies: Raman-Scattering and Infrared-Absorption Study of the 1:2:1:2 Structure (Ca1-yYy)Sr2(Tl0.5Pb0.5)Cu2O7 as a Function of Doping

Authors:: Mertelj, T.; Mihailovič, D.; Matacotta, F.C.; Liu, R.S.; Cooper, John Robert (7044); Gameson, I.; Edwards, P.P.

Journal: Phys.Rev.B
ISSN: 0163-1829
Volume: 47
Year: 1993
Pages: from 12104 to 12109
Number of references: 26
Language: engleski

Title: Magnetic Field Dependence of Phase Coherence Length in the Spin-Density Wave State of (TMTSF)2NO3

Authors:: Biškup, Neven (179286); Basletić, Mario (197593); Tomić, Silvia (65594); Korin-Hamzić, Bojana (61314); Maki, K.; Bechgaard, K.; Fabre, J.M.

Journal: Phys.Rev.B
Number: 13
ISSN: 0163-1829
Volume: 47
Year: 1993
Pages: from 8289 to 8292
Number of references: 19
Language: engleski
Summary: We have used electric-field-dependent measurements to probe themagnetic-field dependence of the phase-coherence length in thespin-density wave (SDW) state of the organic conductor(TMTSF)2NO3. The threshold electric field increases if a magneticfield is applied in the plane perpendicular to the highlyconducting axis. The magnitude of the increase is angle-dependentand vanishes when the field is applied along the intermediateconductivity axis. This behaviour results from a reduction of thephase-coherence length of the SDW with strongly imperfect nestingin a magnetic field.

Title: Anomalous Magnetoresistance in the Spin-Density Wave State of Tetramethyltetraselenafulvalinium Nitrate, (TMTSF)2NO3: Imperfect Nesting Effects

Authors:: Basletić, Mario (197593); Biškup, Neven (179286); Korin-Hamzić, Bojana (61314); Tomić, Silvia (65594); Hamzić, Amir (15234); Bechgaard, K.; Fabre, J.M.

Journal: Europhysics Letters
ISSN: 0295-5075
Volume: 22
Year: 1993
Pages: from 279 to 285
Number of references: 22
Language: engleski
Summary: We report a study of the transverse-magnetoresistance anisotropyin the spin-density wave phase of the organic conductor(TMTSF)2NO3 at temperatures down to 1.8K and in fields up to6tesla. The transverse magnetoresistance is highly anisotropicand obeys a temperature and angular dependent power lawbehaviour. The indication of a possible field-induced SDW phaseis discussed. We suggest that the SDW with large imperfectnesting together with a periodic anion potential might beresponsible for the observed magnetic field effects.
Keywords: low-dimensional conductors, spin-density waves, magnetoresistance, imperfect nesting

Title: No Far-Infrared-Spectroscopic Gap in Clean and Dirty High-Tc Superconductors

Authors:: Mandrus, D.; Martin, M.C.; Kendziora, C.; Koller, D.; Forro, L. (114515); Mihaly, L.

Journal: Phys.Rev.Lett.
ISSN: 0031-9007
Volume: 70
Year: 1993
Pages: from 2629 to 2632
Number of references: 24
Language: engleski
Summary: We report far-infrared transmission measurements on singlecrystal samples derived from Bi2Sr2CaCu2O8. The impurityscattering rate of teh samples was varied by electron-beamirradiation, 50MeV16O6 ion irradiation, heat treatement invacuum, and Y doping. Although substantial changes in theinfrared spectra were produced, in no case was a feature observedthat could be associated with the superconducting energy gap.These results all but rule out "clean limit" explanations for theabsence of the spectroscopic gap in this material, and provideevidence that the superconductivity in Bi2Sr2CaCu2O8 is gapless.

Title: Conduction Electron Spin Resonance in Rb3C60

Authors:: Janossy, A.; Chauvet, O.; Pekker, S.; Cooper, John Robert (7044); Forro, L. (114515)

Journal: Phys.Rev.Lett.
ISSN: 0031-9007
Volume: 71
Year: 1993
Pages: from 1091 to 1094
Language: engleski

Title: Electronic Specific Heat of Yba2Cu3O6+x from 1.8K to 300K

Authors:: Loram, J.W.; Mirza, K.A.; Cooper, John Robert (7044); Liang, W.

Journal: Phys.Rev.Lett.
ISSN: 0031-9007
Volume: 71
Year: 1993
Pages: from 1740 to 1743
Number of references: 23
Language: engleski
Summary: We have determined for the first time the 'electronic' specificheat coefficient of YBa2Cu3O6+x for 0.160.9. However, the continuousdevelopment of the entrpy S(x,Y) with x and T across the entireseries suggests a progressive modification of the low energy spinspectrum with hole doping rather than a simple band model. Fermistatistics and k-space pairing are indicated by the magnitude andT dependence od S(x,T).

Title: Slow and Fast Quantum Oscillations in the High-Field Magnetoresistance of (TMTSF)2NO3:Magnetic Breakthrough Linked to SDW Gap Opening

Authors:: Audouard, A.; Goze, F.; Dubois, S.; Ulmet, J.P.; Brossard, L.; Askenazy, S.; Tomić, Silvia (65594); Fabre, J.M.

Journal: Europhysics Letters
Number: 5
ISSN: 0295-5075
Volume: 25
Year: 1994
Pages: from 363 to 368
Number of references: 33
Language: engleski
Summary: We report a study of the transverse magnetoresistance in the spin-density-wave state of the organic conductor (TMTSF)2NO3 at ambient pressure,in fields up to 37T. For field along the lowest conductivity axis (c*) two series of quantum oscillations, with temperature independent frequencies of 63T and 248T, respectively, are observed in the 2-12K temperature range.The oscillation amplitude of both series decreases when the temperature departs from 4.2K.
Keywords: Measurement of Fermi surface parameters, Spin-density waves, Collective modes, low-dimensional conductors

Title: Commensurate Spin-Density Wave State in (TMTTF)2Br: Single-Particle and Collective Charge Dynamics

Authors:: Tomić, Silvia (65594); Biškup, Neven (179286); Dolanski Babić, Sanja (188231); Maki, K.

Journal: Europhysics Letters
Number: 4
ISSN: 0295-5075
Volume: 26
Year: 1994
Pages: from 295 to 301
Number of references: 24
Language: engleski
Summary: We report the first transport characterization of a unique commensurate spin-density wave state of the organic charge insulator (TMTTF)2Br. Non-Ohmic current-voltage characteristics with sharp threshold fields of the order of 1-10V/cm are observed in the SDW state. Properties of the low-frequency dielectric response and the sliding state indicate a novel charge dynamics associated with this SDW condensate.
Keywords: Spin-density waves, Collective modes, low-dimensional conductors, conductivity of specific semiconductors and insulators

Title: Slow quantum oscillations in the semimetallic spin-density-wave state of (TMTSF)2NO3

Authors:: Biškup, Neven (179286); Balicas, L.; Tomić, Silvia (65594); Jerome, D.; Fabre, J.M.

Journal: Phys.Rev.B
Number: 17
ISSN: 0163-1829
Volume: 50
Year: 1994
Pages: from 12721 to 12725
Number of references: 21
Language: engleski
Summary: We have observed a clear series of fine structures superposed on the angular dependence of the transverse magnetoresistance in the semimetallic spin-density-wave state of the organic conductor (TMTSF)2NO3. An observed asymmetry in the magnitude is due to the striking angular dependence of the ascillations amplitude. The oscillatory phenomenon (Bs=63T) is considered to result from the orbit quantization inside the closed parts of the Fermi surface which are due to the 2kF anion ordering together with the imperfect spin-density-wave nesting.
Keywords: Measurement of Fermi surface parameters, spin-density waves, low-dimensional conductors

Title: Spin-density-wave state of tetramethyltetraselenafulvalinium phosphate (TMTSF)2PF6: Pressure and magnetic-field effects

Authors:: Biškup, Neven (179286); Tomić, Silvia (65594); Jerome, D.

Journal: Phys.Rev.B
Number: 24
ISSN: 0163-1829
Volume: 51
Year: 1994
Pages: from 17972 to 17975
Number of references: 13
Language: engleski
Summary: We have used electrical transport measurements to investigate the pressure-temperature phase diagram in the spin-density-wave phase of the organic conductor tetramethyltetraselenafulvalinium phosphate. The transition temperature and the activation energy both decrease with increasing pressure and increase in magnetic field. This behaviour results from a change of the degree of nesting and is well described within the imperfect nesting theory.
Keywords: spin-density waves, low-dimensional conductors, conductivity, pressure and magnetic field effects

Title: Magnetic susceptibilities, crytical fields and critical currents of Co and Zn doped YBa2Cu3O7

Authors:: Zheng, D.; Campbell, A.M.; Johnson, J.D.; Cooper, John Robert (7044); Porch, A.; Freeman, P.

Journal: Phys.Rev.B
Number: 2
ISSN: 0163-1829
Volume: 49
Year: 1994
Pages: from 1417 to 1426
Number of references: 54
Language: engleski
Summary: We have performed ac susceptibility, dc magnetization and critical-current measurements on a series of YBa2Cu3O7 samples with low levels of Co and Zn doping. We have shown that because of their different substituting sites Co and Zn affect the properties of YBCO differently.
Keywords: high-temperature superconductors, magnetic properties, critical currents


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