53

R. S. Gonnelli, D. Daghero, A. Calzolari, G. A. Ummarino, Valeria Dellarocca, V. A. Stepanov,
S. M. Kazakov, J. Karpinski, C. Portesi, E. Monticone, V. Ferrando, C. Ferdeghini

Point-contact spectroscopy in MgB₂: from fundamental physics to thin-film characterization

Superconductors: Science and Technology, 17, S93–S100 (2004)

54

D. Daghero, R. S. Gonnelli, G. A. Ummarino, A. Calzolari, Valeria Dellarocca, V. A. Stepanov,
V. B. Filippov, Y. B. Paderno

Andreev-reflection spectroscopy of the gap in ZrB₁₂ single crystals

Superconductors: Science and Technology, 17, S250–S254 (2004)

55

R. S. Gonnelli, D. Daghero, A. Calzolari, G. A. Ummarino, Valeria Dellarocca, V. A. Stepanov,
J. Jun, S. M. Kazakov, J. Karpinski

The magnetic-field dependence of the gaps in a two-band superconductor:
a point-contact study of MgB₂ single crystals

Physical Review B, 69, 100504 (2004)

56

G. A. Ummarino, R. S. Gonnelli, S. Massidda, A. Bianconi

Two-band Eliashberg equations and the experimental T_c of the diboride Al_xMg_1-xB₂

Physica C, 407, 121-127 (2004)

57

R. S. Gonnelli, D. Daghero, G. A. Ummarino, Valeria Dellarocca,
A. Calzolari, V. A. Stepanov, J. Jun, S. M. Kazakov, J. Karpinski

Directional point-contact spectroscopy of MgB₂ single crystals in magnetic fields:
two-band superconductivity and critical fields

Physica C, 408-410, 796-798 (2004)

58

D. Daghero, R. S. Gonnelli, G. A. Ummarino, O. V. Dolgov, J. Kortus, A. A. Golubov, S. V. Shulga

The determination of the electron-phonon interaction from tunneling data
in the two-band superconductor MgB₂

Physica C, 408-410, 353-354 (2004)

59

G. A. Ummarino, A. Calzolari, D. Daghero, R. S. Gonnelli, V. A. Stepanov, R. Masini, Maria Roberta Cimberle

Point-contact study of gap amplitude and symmetry in RuSr₂GdCu₂O₈

Institute of Physics Conference Series, vol. 181, 1146-1153 – ISSN: 0951-3248 (2004)

60

R. S. Gonnelli, D. Daghero, A. Calzolari, G. A. Ummarino, Valeria Dellarocca,
V. A. Stepanov, S. M. Kazakov, N. D. Zhigadlo, J. Karpinski

Evidence for single-gap superconductivity in Mg(B_1-xC_x)₂ single crystals with x=0.132
from point-contact spectroscopy

Physical Review B, 71, 060503R (2005)

61

G. A. Ummarino, D. Daghero, R. S. Gonnelli, A. H. Moudden

A study of carbon substitutions in MgB₂ within the two-band Eliashberg theory

Physical Review B, 71, 134511 (2005)

62

J. Karpinski, N. D. Zhigadlo, G. Schuck, S. M. Kazakov, B. Batlogg, K. Rogacki, R. Puzniak,
J. Jun, E. Muller, P. Wagli, R. S. Gonnelli, D. Daghero, G. A. Ummarino, V. A. Stepanov

Al substitution in MgB₂ crystals: influence on superconducting and structural properties

Physical Review B, 71, 174506 (2005)

63

D. Daghero, R. S. Gonnelli, A. Calzolari, G. A. Ummarino, Valeria Dellarocca,
V. A. Stepanov, N. D. Zhigadlo, S. M. Kazakov, J. Karpinski

The superconducting gaps of C-substituted and Al-substituted MgB₂ single crystals
by point-contact spectroscopy

Proceedings of E-MRS Fall Meeting 2004,
Physica Status Solidi C, 2, 1656 (2005)

64

G. A. Ummarino

Pressure dependence of critical temperature in MgB₂ and two-band Eliashberg theory

Physica C, 423, 96 (2005)

65

G. A. Ummarino, R. S. Gonnelli, A. Bianconi

Experimental T_c in doped MgB₂ and two-band Eliashberg theory

Journal of Superconductivity, 18, 191-195 (2005)

66

R. S. Gonnelli, D. Daghero, G. A. Ummarino, A. Calzolari, M. Tortello,
V. A. Stepanov, N. D. Zhigadlo, S. M. Kazakov, J. Karpinski

Evidence for one-gap superconductivity in Mg(B_1-xC_x)₂ single crystals at x=0.132
by point-contact spectroscopy

Journal of Superconductivity, 18, 81-85 (2005)

67

A. Calzolari, D. Daghero, R. S. Gonnelli, G. A. Ummarino, V. A. Stepanov,
R. Masini, Maria Roberta Cimberle, M. Ferretti

Andreev-reflection measurements in RuSr₂GdCu₂O₈

Journal of Physics and Chemistry of Solids, 67, 597-600 (2006)

68

R. S. Gonnelli, D. Daghero, G. A. Ummarino, A. Calzolari, Valeria Dellarocca,
V. A. Stepanov, S. M. Kazakov, J. Jun, J. Karpinski

A point-contact study of the superconducting gaps
in Al-substituted and C-substituted MgB₂ single crystals

Journal of Physics and Chemistry of Solids, 67, 360-364 (2006)

69

D. Daghero, R. S. Gonnelli, G. A. Ummarino, A. Calzolari, Valeria Dellarocca,
V. A. Stepanov, S. M. Kazakov, J. Jun, J. Karpinski

Effect of the magnetic field on the gaps of MgB₂: a directional point-contact study

Journal of Physics and Chemistry of Solids, 67, 424-427 (2006)

70

D. Daghero, R. S. Gonnelli, A. Calzolari, G. A. Ummarino, M. Tortello, V. A. Stepanov,
N. D. Zhigadlo, K. Rogacki, J. Karpinski, M. Putti

Point-contact spectroscopy in doped and irradiated MgB₂

CIMTEC Acireale 2006, Techna Group, Faenza, Italy,
Advances in Science and Technology, 47, 75-81 (2006)

71

R. S. Gonnelli, D. Daghero, G. A. Ummarino, A. Calzolari, M. Tortello, V. A. Stepanov,
N. D. Zhigadlo, K. Rogacki, J. Karpinski

The effect of magnetic impurities in a two-band superconductor:
a point-contact study of Mn-substituted MgB₂ single crystals

Physical Review Letters, 97, 037001 (2006)

72

G. Ghigo, G. A. Ummarino, R. Gerbaldo, L. Gozellino, F. Laviano, E. Mezzetti

Effects of disorder on the microwave properties of MgB₂ polycrystalline films

Physical Review B, 74, 184518 (2006)

73

R. S. Gonnelli, D. Daghero, A. Calzolari, G. A. Ummarino, M. Tortello, V. A. Stepanov,
N. D. Zhigadlo, K. Rogacki, J. Karpinski, C. Portesi, E. Monticone, D. Mijatovic, D. Veldhuis, A. Brinkman

Recent achievements in MgB₂ physics and applications:
a large-area SQUID magnetometer and point-contact spectroscopy measurements

Physica C, 435, 59 (2006)

74

D. Daghero, A. Calzolari, G. A. Ummarino, M. Tortello, R. S. Gonnelli, V. A. Stepanov,
C. Tarantini, P. Manfrinetti, E. Lehmann

Point-contact spectroscopy in neutron irradiated Mg¹¹B₂

Physical Review B, 74, 174519 (2006)

75

R. S. Gonnelli, D. Daghero, G. A. Ummarino, M. Tortello, Debora Delaude, V. A. Stepanov, J. Karpinski

Point-contact Andreev-reflection spectroscopy in MgB₂: the role of substitutions

Physica C, 456, 134-143 (2007)

76

E. Cappelluti, G. A. Ummarino

Strong–coupling properties of unbalanced Eliashberg superconductors

Physical Review B, 76, 104522 (2007)

77

D. Daghero, A. Calzolari, Debora Delaude, R. S. Gonnelli, M. Tortello, G. A. Ummarino,
V. A. Stepanov, N. D. Zhigadlo, J. Karpinski, M. Putti

Point-contact study of the role of non-magnetic impurities
and disorder in the superconductivity of MgB₂

Physica C, 460-462, 975-976 (2007)

78

G. Ghigo, D. Andreone, R. Gerbaldo, L. Gozzelino, F. Laviano, G. Lopardo,
B. Minetti, E. Monticone, G. A. Ummarino, E. Mezzetti

Effects of disorder on the performance of magnesium diboride microwave resonators

IEEE Transactions on Applied Superconductivity, vol. 17, issue 2, part 3, 3644-3647 (2007)

79

D. Daghero, A. Calzolari, M. Tortello, G. A. Ummarino, R. S. Gonnelli, V. A. Stepanov,
N. D. Zhigadlo, K. Rogacki, J. Karpinski

Point-contact spectroscopy in Mn-doped MgB₂ single crystals:
effects of magnetic impurities in a two-band superconductor

Journal of Superconductivity and Novel Magnetism, vol. 20, issue 7-8, 523-526 (2007)

80

R. S. Gonnelli, A. Calzolari, D. Daghero, Debora Delaude, M. Tortello, G. A. Ummarino,
V. A. Stepanov, N. D. Zhigadlo, J. Karpinski, P. Manfrinetti

Effect of heavy Al doping on MgB₂: a point-contact study of crystals and polycrystals

Journal of Superconductivity and Novel Magnetism, vol. 20, issue 7-8, 555-558 (2007)

81

G. A. Ummarino

Effects of magnetic impurities on two-band superconductors

Journal of Superconductivity and Novel Magnetism, vol. 20, issue 7-8, 639-642 (2007)

82

F. Jutier, G. A. Ummarino, J. C. Griveau, F. Wastin, E. Colineau, J. Rebizant, N. Magnani, R. Caciuffo

Mechanism of superconductivity in PuCoGa₅ probed by self-irradiation-damage

Physical Review B, 77, 024521 (2008)

83

D. Daghero, Debora Delaude, A. Calzolari, M. Tortello, G. A. Ummarino, R. S. Gonnelli,
V. A. Stepanov, N. D. Zhigadlo, S. Katrych, J. Karpinski

Point-contact Andreev-reflection spectroscopy
in segregation-free Mg_1-xAl_xB₂ single crystals up to x=0.32

Journal of Physics: Condensed Matter, 20, 085225 (2008)

84

R. S. Gonnelli, D. Daghero, Debora Delaude, M. Tortello, G. A. Ummarino, V. A. Stepanov,
J. S. Kim, R. K. Kremer, A. Sanna, G. Profeta, S. Massidda

Evidence for gap anisotropy in CaC₆ from directional point-contact spectroscopy

Physical Review Letters, 100, 207004 (2008)

85

D. Daghero, G. A. Ummarino, M. Tortello, Debora Delaude, R. S. Gonnelli, V. A. Stepanov, M. Monni, A. Palenzona

Effect of Li-Al co-doping on the energy band of MgB₂

Superconductors: Science and Technology, 22, 025012 (2009)

86

G. A. Ummarino, N. Magnani, J. C. Griveau, J. Rebizant, R. Caciuffo

d-wave superconductive gap and related oservables of PuCoGa₅

Journal of Nuclear Materials, 385, 4-7 (2009)

87

M. Bonura, A. Agliolo Gallitto, M. Li Vigni, G. A. Ummarino

Field-induced suppression of the π-band superconductivity and magnetic hysteresis
in the microwave surface resistance of MgB₂ at temperatures near T_c

Superconductors: Science and Technology, 22, 055010 (2009)

88

L. Gozzelino, B. Minetti, G. A. Ummarino, R. Gerbaldo, G. Ghigo, F. Laviano, G. Lopardo,
G. Giunchi, E. Perini, E. Mezzetti

Intraband scattering rate and electronic diffusivity study in MgB₂ bulk samples

Superconductors: Science and Technology, 22, 065007 (2009)

89

G. A. Ummarino

Iron based layered compounds: the effect of negative interband coupling

Journal of Superconductivity and Novel Magnetism (accepted)

90

R. S. Gonnelli, D. Daghero, M. Tortello, G. A. Ummarino, V. A. Stepanov, R. K. Kremer, J. S. Kim,
N. D. Zhigadlo, J. Karpinski

Point-contact Andreev-reflection spectroscopy in ReFeAsO_1-xF_x (Re = La, Sm):
possible evidence for two nodeless gaps

Physica C (accepted)

91

R. Caciuffo, N. Magnani, G. A. Ummarino, E. Colineau, J. C. Griveau, J. Rebizant, F. Wastin

Superconductivity without phonons in PuCoGa₅ ?

Physica B (accepted)

92

R. S. Gonnelli, M. Tortello, D. Daghero, G. A. Ummarino, V. A. Stepanov, J. S. Kim

Two-gap superconductivity in the Fe-1111 superconductor LaFeAsO_1-xF_x:
a point-contact Andreev-reflection study

Central European Journal of Physics (accepted)

93

R. S. Gonnelli, D. Daghero, M. Tortello, G. A. Ummarino, V. A. Stepanov, J. S. Kim, R. K. Kremer

Point-contact Andreev-reflection spectroscopy in the iron-based superconductor LaFeAsO_1-xF_x:
coexistence of two order parameters and a pseudogap

Journal of Superconductivity and Novel Magnetism (accepted)

94

R. S. Gonnelli, D. Daghero, M. Tortello, G. A. Ummarino, V. A. Stepanov, J. S. Kim, R. K. Kremer

Coexistence of two order parameters and a pseudogap
in the iron-based superconductor LaFeAsO_1-xF_x

Physical Review B (accepted)