Positron Group Publications
Elliptical hole pockets in the Fermi surfaces of unhydrated and hydrated sodium cobalt oxides
J. Laverock, S. B. Dugdale, J. A. Duffy, J. Wooldridge, G. Balakrishnan, M. R. Lees, G.-q. Zheng, D. Chen, C. T. Lin, A. Andrejczuk, M. Itou, and Y. Sakurai
Phys. Rev. B 76 052509 (2007).
Free volume in poly(n-alkyl methacrylate)s from positron lifetime and PVT experiments and its relation
to the structural relaxation
D Kilburn, G Dlubek, J Pionteck and MA Alam
Polymer 47 7774 (2006)
Organization and mobility of water in amorphous and crystalline trehalose
D Kilburn, S Townrow, V Meunier, R Richardson, A Alam and J Ubbink
Nature Materials 5 632 (2006)
Positron/positromum annihilation as a probe for chemical environments of free volume holes in fluoropolymers
D Bamford, G Dlubek, G Dommet, S Horing, T Lupke, D Kilburn and MA Alam
Polymer 47 3486 (2006)
Temperature and pressure dependence of the free volume in polyisobutylene from positron lifetime
and pressure-volume-temperature experiments
D Kilburn, J Wawryszczuk, G Dlubek, J Pionteck, R Hassler and MA Alam
Macromolecular Chemistry And Physics 207 721 (2006)
Free volume, glass transition and degree of branching in ethylene/alpha-olefin copolymers:
Positron lifetime, differential scanning calorimetry, wide-angle X-ray scattering, and density studies
D Bamford, G Dlubek, T Lupke, D Kilburn, J Stejny, TJ Menke and MA Alam
Macromolecular Chemistry And Physics 207 492 (2006)
Observation of a strongly nested fermi surface in the shape-memory alloy Ni0.62Al0.38
SB Dugdale, RJ Watts, J Laverock, Z Major, MA Alam, M Samsel-Czekala, G Kontrym-Sznajd,
Y Sakurai, M Itou and D Fort
Physical Review Letters 96 046406 (2006)
The temperature and pressure dependence of the free volume in fluoroelastomers from PALS and PVT experiments
G Dlubek, A Sen Gupta, J Wawryszczuk, D Kilburn, J Pionteck, R Krause-Rehberg, T Goworek,
MA Alam, H Kaspar and KH Lochhaas
Acta Physica Polonica A 107 685 (2005)
Temperature and pressure dependence of alpha-relaxation and free volume in poly(vinyl acetate)
G Dlubek, D Kilburn and MA Alam
Macromolecular Chemistry And Physics 206 818 (2005)
Fermi-surface effect on magnetic interlayer coupling
E. Holmström, A. Bergman, L. Nordström, I.A. Abrikosov, S.B. Dugdale
and B.L. Györffy
Phys. Rev. B 70 064408 (2004).
Evolution of the Fermi surface and the oscillatory exchange coupling across Cr and Cr-based alloys
R.J. Hughes, S.B. Dugdale, Zs. Major, M.A. Alam, T. Jarlborg, E. Bruno and
B. Ginatempo
Phys. Rev. B 69 174406 (2004).
Refining Fermi surface topologies from ab initio calculations through momentum density spectroscopies
Zs. Major, S.B. Dugdale, R.J Watts, J. Laverock, J.J. Kelly, D.C.R. Hedley and M.A. Alam
J. Phys. Chem. Solids.65 2011 (2004)
Direct observation of the multi-sheet Fermi surface in the strongly correlated transition metal compound ZrZn2
Zs. Major, S.B. Dugdale, R.J. Watts, G. Santi, M.A. Alam, S.M. Hayden, J.A. Duffy, J.W. Taylor, T. Jarlborg,
E. Bruno, D. Benea and H. Ebert
Phys. Rev. Lett. 92 107003 (2004).
The structure of the free volume in SAN copolymers from positron lifetime and PVT experiments
I. Free volume from the Simha-Somcynsky analysis of PVT experiments
G. Dlubek, J. Pionteck and D. Kilburn
Macromol. Chem. Phys. 205 500 (2004)
The structure of the free volume in SAN copolymers from positron lifetime and PVT experiments
II. Local free volume from postiron annihilation lifetime spectroscopy (PALS)
G. Dlubek, V. Bondarenko, I.Y. al-Qaradawi, D. Kilburn and R. Krause-Rehberg
Macromol. Chem. Phys. 205 512 (2004)
Electronic topological transitions, magnetic ordering and the Fermi surfaces of Y and the heavy rare earths
S.J. Crowe, S.B. Dugdale, Zs. Major, M.A. Alam, J.A. Duffy and S.B. Palmer
Europhysics Letters 65 235 (2004).
The size and number of local free volumes in polypropylenes: A positron lifetime and PVT study
J.D. Kilburn, D. Bamford, G. Dlubek, J. Pionteck and M.A. Alam
Polym. Sci. B: Pol. Phys. 41 3089 (2003)
Differential scanning calorimetry (DSC) for interdiffusion studies in PVC/PnBMA blend: A quantitative analysis
G. Dlubek, G. Pompe, J. Pionteck, A. Janke and D. Kilburn
Macromolecular Chemistry and Physics 204 (9): 1234-1244 (2003).
Studies of interdiffusion in polymer blends by PALS
G. Dlubek, V. Bondarenko, J. Pionteck, D. Kilburn, G. Pompe, C. Taesler, F. Redmann,
K. Petters, R. Krause-Rehberg, M.A. Alam
Radiation Physics and Chemistry 68 (3-4): 369-373 2003.
Ionic conductivity, glass transition, and local free volume in poly(ethylene oxide) electrolytes: Single and mixed ion conductors
D. Bamford, A. Reiche, G. Dlubek, et al.
J. Chem. Phys. 118 (20): 9420 (2003)
Heavy quasiparticles in the ferromagnetic superconductor ZrZn2
S.J.C. Yates, G. Santi, S.M. Hayden, P.J. Meeson and S.B. Dugdale
Phys. Rev. Lett. 90 057003 (2003).
The electronic structure of ordered and disordered Fe3Pt
Zs. Major, S.B. Dugdale, T. Jarlborg, E. Bruno, B. Ginatempo, J. Poulter and J.B. Staunton.
J. Phys.: Condens. Matter 15 3619 (2003).
The EMD-LMTO program for electron-positron momentum density calculations in solids
B. Barbiellini, S.B. Dugdale and T. Jarlborg
Computational Materials Science 28 287 (2003).
Free volume, glass transition, and degree of branching in metallocene-based propylene/alpha-olefin copolymers:
Positron lifetime, density, and differential scanning calorimetric studies
G. Dlubek, D. Bamford, A. Rodriguez-Gonzalez, S. Bornemann, J. Stejny, B. Schade,
M.A. Alam and M. Arnold
J. Polym. Sci. Pol. Phy. 40 (5): 434-453 (2002).
Studies of positron lifetime and Doppler-broadened annihilation radiation of polypropylene-polystyrene alloys
G. Dlubek and M.A. Alam
Polymer 43 4025-4031 (2002).
Free volume and glass transition in ethylene/1-octene copolymers: positron lifetime studies and dynamic mechanical analysis
D. Kilburn, D. Bamford, T. Lupke, G. Dlubek, T.J. Menke and M.A. Alam
Polymer 43 (25): 6973-6983 (2002).
Free-volume variation in polyethylenes of different crystallinities : Positron lifetime, density and x-ray studies
G. Dlubek, J. Stejny, Th. Lüpke, D. Bamford, K. Petters,
Ch. Huebner, M.A. Alam and M.J. Hill
J. Polymer Science B 39 65 (2002).
Local free volume and glass transition in propylene/alpha-olefin copolymers with a defined length and number of branches
G. Dlubek, D. Bamford, A. Rodriguez-Gonzalez, et al.
Mater Sci Forum 363-3: 303-305 (2001).
Longitudinal spin-fluctuations and superconductivity in ferromagnetic ZrZn2 from ab initio calculations
G. Santi, S.B.Dugdale and T. Jarlborg
Phys. Rev. Lett. 87 247004 (2001).
Fermi surface nesting in disordered Cu1-xPdx alloys
I. Wilkinson, R.J. Hughes, Zs. Major, S.B. Dugdale, M.A. Alam,
E. Bruno, B. Ginatempo and E.S. Giuliano
Phys. Rev. Lett. 87 216401 (2001).
Electronic structure, magnetism and superconductivity of MgCxNi3
S.B. Dugdale and T. Jarlborg
Phys. Rev. B 64 100508(R) (2001).
Magnetic Compton scattering study of the ferromagnetic amorphous alloys Fe1-xBx
J.W. Taylor, J.A. Duffy, A.M. Bebb, M.J. Cooper, S.B. Dugdale, J.E. McCarthy, D.N. Timms,
D. Greig and Y. Xu
Phys. Rev. B 63 220404(R) (2001).
The local free volume in metallocene-catalysed poly(alpha-olefin)s: A positron lifetime study
G. Dlubek, D. Bamford, O. Henscke, J. Knorr, M.A. Alam, M. Arnold and
Th. Lüpke
Polymer 42 5381 (2001).
Anisotropic nature of open volume 'defects' in highly crystalline polyethylene fibres
D. Bamford, M. Jones, J. Latham, M.A. Alam, R.J. Hughes, J. Stejny
and G. Dlubek
Macromolecules 34 8156 (2001).
The local free volume, glass transition, and ionic conductivity in a polymer electrolyte : A positron lifetime study
D. Bamford, G. Dlubek, A. Reiche, M.A. Alam, W. Meyer, P. Galvosas and
F. Rittig
J. Chem. Phys. 115 7260 (2001).
Induced spin polarization in ferromagnetic Gd62.4Y37.6
J.A. Duffy, S.B. Dugdale, J.E. McCarthy, M.A. Alam, M.J. Cooper, S.B. Palmer
and T. Jarlborg
Phys. Rev. B 61 14331 (2000).
Freezing and melting behavior of CO2 in nanometer geometry
J.A. Duffy and M.A. Alam
Langmuir 16 9513 (2000).
Capillary condensation and desorption of binary mixtures of N2-Ar confined in a mesoporous medium
M.A. Alam, A.P. Clarke and J.A. Duffy
Langmuir 16 7551 (2000).
Local free volume in ethylene-vinyl acetate copolymers : a positron lifetime study
G. Dlubek, Th. Lüpke, J. Stejny, M.A. Alam and M. Arnold
Macromolecules 33 990 (2000).
A high-resolution Compton scattering study of the Fermi surface of chromium
S.B.Dugdale, H.M. Fretwell, K.J. Chen, Y. Tanaka, A. Shukla, T. Buslaps, Ch. Bellin,
G. Loupias, M.A. Alam, A.A. Manuel, P. Suortti, N. Shiotani
Journal of Physics and Chemistry of Solids 61 361 (2000).
Positron/Positronium annihilation as a probe of the chemical environment of free volume holes in polymers
G. Dlubek, H.M. Fretwell and M.A. Alam
Macromolecules 33 187 (2000).
Nesting properties and anisotropy of the Fermi surface of LuNi2B2C
S.B.Dugdale, M.A. Alam, I. Wilkinson, R.J. Hughes, I.R. Fisher, P.C. Canfield, T. Jarlborg
and G. Santi
Phys. Rev. Lett. 83 4824 (1999).
Fermi surface of the colossal magnetoresistance perovskite La0.7Sr0.3MnO3
E.A.Livesay, R.N.West, S.B.Dugdale, G.Santi and T.Jarlborg
J.Phys.:Condens. Matter 11 L279 (1999).
The local free volume in blends of acrylonitrile-butadiene-styrene co-polymers and polyamide-6
G. Dlubek, M.A. Alam, M. Stolp and H.J. Radusch
J. Pol. Sci. B: Polymer Physics 37 1749 (1999).
Fermi surface as the driving mechanism for helical antiferromagnetic ordering in Gd-Y alloys
H.M.Fretwell, S.B.Dugdale,M.A. Alam,D.C.R.Hedley, A.Rodriguez-Gonzalez
and S.B.Palmer
Phys. Rev. Lett. 82 3867 (1999).
Investigation of thermotropic phase transitions in a triple chain amphiphile forming hexagonal columnar
and inverse micellar cubic mesophases - A positron annihilation lifetime study
G.Dlubek, D.Bamford, I.Wilkinson, K.Borisch, M.A.Alam and C.Tschierske
Liquid Crystals 26 863 (1999).
Thermal disorder versus correlation in Compton profiles from alkali metals
S.B.Dugdale and T.Jarlborg
Solid State Commun. 105 283 (1998).
Spin density in ferromagnetic nickel : a magnetic Compton scattering study
M.A.G.Dixon, J.A.Duffy, S.Gardelis, J.E.McCarthy, M.J.Cooper, S.B.Dugdale, T.Jarlborg and D.N.Timms.
J.Phys.:Condens. Matter 10 2759 (1998).
The effect of crosslinking on the free volume properties of diethylene glycol bis(allylcarbonate) polymer networks:
a positron annihilation lifetime study.
G.Dlubek, J. Stejny and M.A.Alam.
Macromolecules 31 4574 (1998).
The local free volume in deformed polyethylene: a positron lifetime study
G.Dlubek, T.Lupke, H.M.Fretwell, M.A. Alam, A.Wutzler and H.Radusch
Acta Polymerica 49 236
(1998).
Femiology of Cr and Mo
S.B.Dugdale, H.M.Fretwell, D.C.R.Hedley, M.A.Alam, T.Jarlborg,
G.Santi, R.M.Singru, V.Sundararajan and M.J.Cooper
J.Phys.:Condens. Matter 10 10367
(1998).
Fermi surface callipering of Cr alloys
H.M.Fretwell, S.B.Dugdale, R.J.Hughes, J.Brader, M.A.Alam and A.Rodriguez-Gonzalez
J.Phys.:Condens. Matter 10 10375
(1998).
Spin density in Gd studied by magnetic Compton scattering
J.A.Duffy, J.E.McCarthy, S.B.Dugdale, V.Honkimaki, M.J.Cooper,
M.A.Alam, T.Jarlborg and S.B.Palmer
J.Phys.:Condens. Matter 10 10391
(1998).
Effect of crystallisation and of water up-take on the free volume hole size in the polyamides 6 and 66
G.Dlubek, M.Stolp, Ch.Nagel., H.M.Fretwell, M.A.Alam and H.J.Radusch
J.Phys.:Condens. Matter 10 10443
(1998).
Fermi surface reconstruction from 2D-ACAR data using maximum-likelihood fitting of wavelet-like functions
A.G.Major, H.M.Fretwell, S.B.Dugdale and M.A.Alam
J.Phys.:Condens. Matter 10 10507
(1998).
The temperature dependence of the local free volumes in polyethylene and polytetrafluorethylyne: a positron lifetime study.
G.Dlubek, K.Saarinen and H.M.Fretwell.
J. Polym. Sci. B: Polym. Phys. 36 1513
(1998).
Positron states in polyethylene and polytetrafluorethylyne: a positron lifetime and Doppler-broadening study.
G.Dlubek, K.Saarinen and H.M.Fretwell.
Nucl. Instr. Meth. in Phys. Res. B 142
139 (1998).
Positron annihilation study of the electronic structure of LaB6.
M.Biasini, M.A.Alam, S.B.Dugdale, H.M.Fretwell,
Y.Kubo, H.Harima and N.Sato.
Appl. Surf. Sci. 116 335 (1997).
Direct observation of the ``webbing'' Fermi surface of yttrium.
S.B.Dugdale, H.M.Fretwell, M.A.Alam, G.Kontrym-Sznajd,
R.N.West and S.Badrzadeh.
Phys. Rev. Lett. 79 941 (1997).
The structure of solid CO2 in porous Vycor glass.
D.W.Brown, P.E.Sokol, A.P.Clarke, M.A.Alam and
W.J.Nuttall.
J.Phys.:Condens. Matt. 9 7317 (1997).
Positron annihilation study of the electronic structure of LaB6 and CeB6.
M.Biasini, H.M.Fretwell, S.B.Dugdale, M.A.Alam,
Y.Kubo, H.Harima and N.Sato.
Phys. Rev. B 56 10192 (1997).
De-noising of 2D-ACAR data using Daubechies wavelet thresholding.
A.G.Major, H.M.Fretwell, S.B.Dugdale, A.Rodriguez-Gonzalez
and M.A.Alam.
J.Phys.:Condens. Matt. 9 10293
(1997).
Positron lifetime studies of free-volume hole size distribution in glassy polycarbonate and polystyrene.
G.Dlubek, A.P.Clarke, H.M.Fretwell, S.B.Dugdale
and M.A.Alam .
Physica Status Solidi A-Applied Research 157
351 (1996).
Positron and positronium annihilation studies of the phase-behaviour of fluids in VYCOR.
H.M.Fretwell, J.A.Duffy, A.P.Clarke, M.A. Alam
and R Evans.
J.Phys.:Condens.Matt. 8 9613 (1996).
Positron Annihilation study of the electronic structure of CeB6, CeCu6 and LaCu6.
M.Biasini, H.Harima, Y.Onuki, H.M.Fretwell, S.B.Dugdale,
M.A.Alam and R.N.West.
Physica B 206-207 40 (1995).
Reconstruction of 3D electron-positron momentum densities from 2D projections:
role of Maximum Entropy deconvolution prior to reconstruction.
H.M.Fretwell, S.B.Dugdale, M.A.Alam, M.Biasini,
L.Hoffmann and A.A.Manuel.
Europhys. Lett. 32 771 (1995).
Hysteresis at the gas-liquid and liquid-solid phase transitions of capillary confined CO2: a positronium annihilation study.
J.A.Duffy, N.J.Wilkinson, H.M.Fretwell and M.A.Alam.
J.Phys.:Condens.Matt. 7 L27 (1995).
Defect annealing and the formation of Li-rich clusters in Al-Li alloys.
H.M. Fretwell, J.A.Duffy, M.A.Alam, H.P.Leighly
Jr and J.Walmsley.
J.Phys.:Condens.Matt. 7 4573 (1995).
Phase-transitions of CO2 confined in nanometre pores as revealed by positronium annihilation.
J.A.Duffy, N.J.Wilkinson, H.M.Fretwell, M.A.Alam
and R.Evans.
J.Phys.:Condens.Matt. 7 L713 (1995).
Deformation-induced microvoids in Bismuth and possible positronium formation.
J.M.Clayton, S.G.Usmar, H.M.Fretwell, I.K.MacKenzie
and M.A.Alam.
J.Phys.:Condens.Matt. 7 3181 (1995).
Hysteresis during isothermal scanning through the gas-liquid phase transition of CO2 confined in nanometre pores.
N.J.Wilkinson, J.A.Duffy, H.M.Fretwell and M.A.Alam.
Phys.Lett.A 204 285 (1995)
Positron annihilation study of the electronic structure of CeCu6 and LaCu6.
M.Biasini, H.M.Fretwell, H.Harima, Y.Onuki, S.B.Dugdale,
M.A.Alam and R.N.West.
Nuovo Cimento 17D 449 (1995).
A Positron Annihilation study of the electronic structure of CeB6.
M.Biasini, M.A.Alam, H.Harima, Y.Onuki, H.M.Fretwell
and R.N.West.
J.Phys.:Condens.Matt. 6 7823 (1994).
Application of Maximum Entropy technique to extract Fermi surface topology from Positron Annihilation measurements.
S.B.Dugdale, M.A.Alam, H.M.Fretwell, M.Biasini
and D.Wilson.
J.Phys.:Condens.Matt. 6 L435 (1994).
A Positron Annihilation study of capillary condensation of nitrogen gas in a mesoporous solid.
N.J.Wilkinson, A.Alam, J.M.Clayton, R.Evans, H.M.Fretwell
and S.G.Usmar.
Phys.Rev.Lett. 69 3535 (1992).