Institiúidí
|
Fúinn
|
Cúnamh
|
English
0
1000
Baile
Brabhsáil
Cuardach Casta
Stair Chuardaigh
Liosta Marcáilte
Staitisticí
A
A
A
Taispeáin roghanna cuardaigh
Folaigh roghanna cuardaigh
Cuardaigh ag úsáid:
Gach
Aon
Dada acu seo
Frása díreach
i
Eochairfhocal (Gach Réimse)
Teideal
Úadar
Suibiacht
Institiúid
Maoinitheoir
Gach
Aon
Dada acu seo
Frása díreach
i
Eochairfhocal (Gach Réimse)
Teideal
Úadar
Suibiacht
Institiúid
Maoinitheoir
Gach
Aon
Dada acu seo
Frása díreach
i
Eochairfhocal (Gach Réimse)
Teideal
Úadar
Suibiacht
Institiúid
Maoinitheoir
Ó
2104
2027
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
1976
1975
1974
1973
1972
1971
1970
1969
1968
1967
1966
1965
1964
1963
1962
1961
1960
1959
1958
1957
1956
1955
1954
1953
1952
1951
1950
1949
1948
1947
1946
1945
1944
1943
1942
1941
1940
1939
1938
1937
1936
1935
1934
1933
1932
1931
1930
1929
1928
1927
1926
1925
1924
1923
1920
1919
1917
1916
1915
1914
1913
1912
1911
1910
1909
1908
1907
1906
1905
1904
1903
1902
1901
1900
1899
1898
1897
1896
1895
1894
1893
1892
1891
1890
1889
1888
1887
1886
1885
1884
1883
1882
1881
1880
1879
1878
1877
1876
1875
1874
1873
1872
1871
1870
1869
1868
1867
1866
1865
1864
1862
1861
1860
1859
1858
1857
1856
1855
1854
1853
1852
1851
1850
1849
1846
1842
1840
1835
1827
1825
1821
1820
1818
1817
1815
1812
1811
1810
1809
1808
1807
1806
1805
1804
1803
1802
1801
1800
1792
1790
1770
1713
1111
1000
Chuig
2019
2104
2027
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
1976
1975
1974
1973
1972
1971
1970
1969
1968
1967
1966
1965
1964
1963
1962
1961
1960
1959
1958
1957
1956
1955
1954
1953
1952
1951
1950
1949
1948
1947
1946
1945
1944
1943
1942
1941
1940
1939
1938
1937
1936
1935
1934
1933
1932
1931
1930
1929
1928
1927
1926
1925
1924
1923
1920
1919
1917
1916
1915
1914
1913
1912
1911
1910
1909
1908
1907
1906
1905
1904
1903
1902
1901
1900
1899
1898
1897
1896
1895
1894
1893
1892
1891
1890
1889
1888
1887
1886
1885
1884
1883
1882
1881
1880
1879
1878
1877
1876
1875
1874
1873
1872
1871
1870
1869
1868
1867
1866
1865
1864
1862
1861
1860
1859
1858
1857
1856
1855
1854
1853
1852
1851
1850
1849
1846
1842
1840
1835
1827
1825
1821
1820
1818
1817
1815
1812
1811
1810
1809
1808
1807
1806
1805
1804
1803
1802
1801
1800
1792
1790
1770
1713
1111
1000
Go roghnach, scag trí:
(Fág gan seiceáil le gach réimse a chuardach)
Cineál Míre
Book
Book chapter
Conference item
Contribution to newspaper/magazine
Doctoral thesis
Journal article
Master thesis (research)
Master thesis (taught)
Multimedia
Patent
Report
Review
Working paper
Other
Stádas Athbhreithnithe Piaraí
Peer reviewed
Non peer reviewed
Unknown
Institiúid
All Ireland Public Health Repository
Connacht-Ulster Alliance
Dublin City University
Dublin Institute of Technology
Dundalk Institute of Technology
Lenus
Marine Institute
Mary Immaculate College
Maynooth University
NUI Galway
Royal College of Surgeons in Ireland
Teagasc
Trinity College Dublin
University College Cork
University College Dublin
University of Limerick
Maoinitheoir
Enterprise Ireland (EI)
Environmental Protection Agency (EPA)
Health Research Board (HRB)
Higher Education Authority (HEA)
Irish Aid
Irish Research Council for Humanities and Social Sciences (IRCHSS)
Irish Research Council for Science Engineering and Technology (IRCSET)
Marine Institute
Science Foundation Ireland (SFI)
Teagasc
Teanga
Irish
English
Bulgarian
Catalan; Valencian
Czech
Danish
Dutch; Flemish
French
German
Greek, Modern (1453-)
Croatian
Interlingue; Occidental
Italian
Japanese
Norwegian
Romanian; Moldavian; Moldovan
Spanish; Castilian
Serbian
Cuardach Reatha:
'physics' i gach réimse;
3195 míreanna faighte
Sortáil de réir
Ábharthacht
Teideal
Úadar
Cineál Míre
Dáta
Institiúid
Stádas Athbhreithnithe Piaraí
Teanga
Ordú
Ord ardaitheach
Ord íslitheach
25
50
100
sa leathanach
1
2
3
4
5
6
7
8
9
10
Bibtex
CSV
Fonóta
Obair Thagartha
RIS
XML
Ag Taispeaint Torthaí 101 - 125 de 3195 ar leathanach 5 de 128
Marcáilte
Marcáil
Magnetic, magnetotransport, and optical properties of Al-doped Zn0.95Co0.05O thin films
(2007)
VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID
Magnetic, magnetotransport, and optical properties of Al-doped Zn0.95Co0.05O thin films
(2007)
VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Thin films of 5% Co-doped ZnO with a range of Al codoping exhibit a band-edge shift, which varies with carrier concentration as n2/3. Carrier effective mass is 0.26me and mobility is ~ 10?cm2?V?1?s?1. The doped films, which contain coherent Co clusters of 4?8?nm in size, exhibit a ferromagnetic moment of 0.3?1.0?B per cobalt. The magnetism is progressively destroyed by Al doping due to a reduction in Co-cluster formation. Magnetoresistance appears below 30?K, but these materials cannot be regarded as dilute magnetic semiconductors.
http://hdl.handle.net/2262/31893
Marcáilte
Marcáil
Influence of annealing on the bias voltage dependence of tunnelling magnetoresistance in MgO double-barrier magnetic tunnel junctions with CoFeB electrodes
(2006)
FENG, GEN; VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Influence of annealing on the bias voltage dependence of tunnelling magnetoresistance in MgO double-barrier magnetic tunnel junctions with CoFeB electrodes
(2006)
FENG, GEN; VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Double-barrier magnetic tunnel junctions with two MgO barriers and three CoFeB layers exhibiting tunneling magnetoresistance (TMR) values of more than 100% were fabricated. The bias voltage dependence of the TMR ratio is highly asymmetric after annealing at low temperatures, indicating dissimilar CoFeB/MgO interfaces. The TMR effect decays very slowly for positive bias and is only reduced to half of its maximum value at V1/2 = 1.88?V when the junctions are processed at 200??C. The largest output voltage, 0.62?V, is obtained after annealing at 300??C, a temperature that combines high TMR ratios with a considerable asymmetric bias dependence.
http://hdl.handle.net/2262/31890
Marcáilte
Marcáil
Point contact Andreev reflection by nanoindentation of polymethyl methacrylate
(2006)
COEY, JOHN MICHAEL DAVID
Point contact Andreev reflection by nanoindentation of polymethyl methacrylate
(2006)
COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
A versatile technique for performing spin polarization measurements via point contact Andreev reflection has been developed. This technique involves depositing a superconductor lead onto a thin film of the material to be studied through a nanohole formed in a layer of photoresist, using an atomic force microscope as a nanoindenter. Copper and nickel were used to demonstrate the method. The polarizations of CrO2 and Co2MnSi were also measured, the former giving a value of 95%, as expected, and the latter giving 20%, which was surprisingly low for a candidate half metal.
http://hdl.handle.net/2262/31889
Marcáilte
Marcáil
Controlled fabrication of nickel perpendicular nanocontacts using focused ion beam milling
(2006)
COEY, JOHN MICHAEL DAVID
Controlled fabrication of nickel perpendicular nanocontacts using focused ion beam milling
(2006)
COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
A method for the controlled fabrication of a nickel perpendicular nanocontact with diameters less than 5 nm is reported. The method involves milling pores through the 100 nm thick silicon nitride membrane using a focused ion beam, and depositing thin Ni film on the both side of the silicon nitride membrane. The shape of the resulting pore and nanocontact size is determined by the initial hole size and redeposition of the sputtered material onto the sidewalls of the holes. A sub-5 nm Ni nanocontact was prepared and the I-V and R-H characteristics measured.
http://hdl.handle.net/2262/31888
Marcáilte
Marcáil
Magnetoresistance of nickel nanocontacts fabricated by different methods
(2006)
COEY, JOHN MICHAEL DAVID
Magnetoresistance of nickel nanocontacts fabricated by different methods
(2006)
COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Nickel nanocontacts have been fabricated by focused ion-beam #1;FIB#2; milling of e-beam patterned planar contacts, FIB milling of conical-shaped nanoperforations in a silicon nitride membrane, and nanoimprinting using an atomic force microscope. Their sizes ranged from 1 to 30 nm. Magnetoresistance of up to 3% is developed in a field of a few millitesla. This is interpreted in terms of ballistic magnetoresistance across a wide domain wall whose structure is determined by dipolar interactions at the contact.
http://hdl.handle.net/2262/31887
Marcáilte
Marcáil
Magnetoresistance and electrical hysteresis in stable half-metallic (La0.7Sr0.3 MnO3 and Fe3O4 nanoconstrictions
(2005)
COEY, JOHN MICHAEL DAVID
Magnetoresistance and electrical hysteresis in stable half-metallic (La0.7Sr0.3 MnO3 and Fe3O4 nanoconstrictions
(2005)
COEY, JOHN MICHAEL DAVID
Achomaireacht:
We have studied the transport properties of mechanically stable Fe3O4 and La0.7Sr0.3MnO3 nanoconstrictions patterned by focused ion-beam milling. The magnetoresistance decreases with the square of the applied voltage and scales with the resistance of the constriction, with values up to 8000% for magnetite and 100% for La0.7Sr0.3MnO3. These results are interpreted within a model for domain-wall magnetoresistance. Some samples exhibit electrical hysteresis with discrete changes of resistance that disappear in the presence of a magnetic field, indicating domain-wall displacement driven by a spin-polarized current.
http://hdl.handle.net/2262/31850
Marcáilte
Marcáil
Magnetite Schottky barriers on GaAs substrates
(2005)
VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Magnetite Schottky barriers on GaAs substrates
(2005)
VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Thin films of HfO2 produced by pulsed-laser deposition on sapphire, yttria-stabilized zirconia, or silicon substrates show ferromagnetic magnetization curves with little hysteresis and extrapolated Curie temperatures far in excess of 400 K. The moment does not scale with film thickness, but in terms of substrate area it is typically in the range 150?400 ?B nm?2. The magnetization exhibits a remarkable anisotropy, which depends on texture and substrate orientation. Pure HfO2 powder develops a weak magnetic moment on heating in vacuum, which is eliminated on annealing in oxygen. Lattice defects are the likely source of the magnetism.
http://hdl.handle.net/2262/31849
Marcáilte
Marcáil
Tunnel magnetoresistance of disordered low-moment Co2MnSi Heusler alloy films
(2005)
VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID
Tunnel magnetoresistance of disordered low-moment Co2MnSi Heusler alloy films
(2005)
VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Thin films of Co(1?x?y)MnxSiy (x = 0.18?0.26 and y = 0.23?0.29) were deposited from elemental targets onto thermal-oxidized Si substrates at room temperature using dc magnetron cosputtering. The as-deposited films appear to be amorphous showing no distinguishable peaks in x-ray diffraction, and the magnetic moment at room temperature is nearly zero. Despite of its low magnetic moment (less than 0.001?B per formula), the disordered Heusler magnetic tunnel junctions show tunnel magnetoresistance ratios as large as 10% at room temperature. The dependence of the tunnel magnetoresistance ratio on compositions x and y is also reported.
http://hdl.handle.net/2262/31848
Marcáilte
Marcáil
IrMn as exchange-biasing material in systems with perpendicular magnetic anisotropy
(2005)
VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
IrMn as exchange-biasing material in systems with perpendicular magnetic anisotropy
(2005)
VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Contact between a Co/Pt multilayer and an IrMn film leads to perpendicular exchange bias. The exchange bias field does not depend on the degree of (111) film texture and for Co/Pt multilayers with IrMn at the bottom it can be enhanced by magnetic field annealing. The perpendicular exchange bias of the Co/Pt?IrMn system is limited by a misalignment between the Co spins and the film normal, which is due to a negative magnetic anisotropy contribution from the Co/IrMn interface (KSCo/IrMn = ?0.09?mJ/m2). The insertion of a 3?? thick Pt layer at the Co/IrMn interface maximizes the perpendicular exchange-bias field.
http://hdl.handle.net/2262/31847
Marcáilte
Marcáil
Correlation between perpendicular exchange bias and magnetic anisotropy in IrMn/[Co/Pt](n) and [Pt/Co](n)/IrMn multilayers
(2005)
VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Correlation between perpendicular exchange bias and magnetic anisotropy in IrMn/[Co/Pt](n) and [Pt/Co](n)/IrMn multilayers
(2005)
VAN DIJKEN, SEBASTIAN; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Perpendicular exchange bias has been observed for IrMn/[Co/Pt]n and [Pt/Co]n/IrMn multilayers in the as-deposited state. The exchange bias field is largest when the IrMn film is grown on magnetically saturated Co/Pt multilayers (8.12?mT for n = 3), whereas it is considerably smaller when domain formation in the IrMn film occurs before Co/Pt deposition (3.30?mT for n = 3). After annealing at 220??C in an out-of-plane magnetic field the perpendicular exchange bias field and magnetic anisotropy are considerably larger for the Co/Pt multilayers with an IrMn film at the bottom. The apparent correlation between bias and anisotropy is explained by the dependence of the perpendicular exchange bias field on the orientation of the Co spins near the Co/IrMn interface.
http://hdl.handle.net/2262/31846
Marcáilte
Marcáil
Influence of the annealing field strength on exchange bias and magnetoresistance of spin valves with IrMn
(2005)
VAN, DIJKEN SEBASTIAN; COEY, JOHN MICHAEL DAVID
Influence of the annealing field strength on exchange bias and magnetoresistance of spin valves with IrMn
(2005)
VAN, DIJKEN SEBASTIAN; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
We report on field annealing effects in spin valves with an IrMn pinning layer and spin valves with a synthetic antiferromagnet. The exchange bias field and magnetoresistance of spin valves with an IrMn/CoFe bilayer at the bottom improve drastically upon annealing in large magnetic fields. The evolution of the exchange bias field with annealing field strength shows a rapid increase up to an applied field of 0.5 T, which is followed by a more gradual improvement up to an annealing field of 5.5 T. The increase of the exchange bias field in large magnetic fields indicates that the interfacial spin structure of the IrMn layer is directly influenced by the annealing field strength.
http://hdl.handle.net/2262/31835
Marcáilte
Marcáil
Annealing of CoFeB/MgO based single and double barrier magnetic tunnel junctions: Tunnel magnetoresistance, bias dependence, and output voltage
(2009)
FENG, GEN; FENG, JIA-FENG; VAN, DIJKEN SEBASTIAN; COEY, JOHN MICHAEL DAVID
Annealing of CoFeB/MgO based single and double barrier magnetic tunnel junctions: Tunnel magnetoresistance, bias dependence, and output voltage
(2009)
FENG, GEN; FENG, JIA-FENG; VAN, DIJKEN SEBASTIAN; COEY, JOHN MICHAEL DAVID
Achomaireacht:
peer-reviewed
Co40Fe40B20/MgO single and double barrier magnetic tunnel junctions (MTJs) were grown using target-facing-target sputtering for MgO barriers and conventional dc magnetron sputtering for Co40Fe40B20 ferromagnetic electrodes. Large tunnel magnetoresistance (TMR) ratios, 230% for single barrier MTJs and 120% for the double barrier MTJs, were obtained after postdeposition annealing in a field of 800 mT. The lower TMR ratio for double barrier MTJs can be attributed to the amorphous nature of the middle Co40Fe40B20 free layer, which could not be crystallized during postannealing. A highly asymmetric bias voltage dependence of the TMR can be observed for both single and double barrier MTJs in the as-deposited states and after field annealing at low temperature. The asymmetry decreases with increasing annealing temperature and the bias dependence becomes almost symmetric after annealing at 350??C. Maximum output voltages of 0.65 and 0.85 V were obtained for both single and...
http://hdl.handle.net/2262/31647
Marcáilte
Marcáil
Effects of excitonic diffusion on stimulated emission in nanocrystalline ZnO
(2006)
LUNNEY, JAMES GERARD
Effects of excitonic diffusion on stimulated emission in nanocrystalline ZnO
(2006)
LUNNEY, JAMES GERARD
Achomaireacht:
peer-reviewed
We present optically pumped emission data for ZnO, showing that high excitation effects and stimulated emission/lasing are observed in nanocrystalline ZnO thin films at room temperature, although such effects are not seen in bulk material of better optical quality. A simple model of exciton density profiles is developed which explains our results and those of other authors. Inhibition of exciton diffusion in nanocrystalline samples compared to bulk significantly increases exciton densities in the former, leading?via the nonlinear dependence of emission in the exciton bands on the pump intensity?to large increases in emission and to stimulated emission.
http://hdl.handle.net/2262/31466
Marcáilte
Marcáil
Alternating and direct current characterization and photoinduced absorption studies of modified conjugated polymer thin films
(2004)
BLAU, WERNER; COLEMAN, JONATHAN NESBIT; DRURY, ANNA
Alternating and direct current characterization and photoinduced absorption studies of modified conjugated polymer thin films
(2004)
BLAU, WERNER; COLEMAN, JONATHAN NESBIT; DRURY, ANNA
Achomaireacht:
Control of interchain separation enables the optical properties of polymer thin films to be altered. We present a thin film preparation technique that increases the free volume fraction in spin coated polymer thin films resulting in reduced interchain interaction. The polaron yield, measured using photoinduced absorption, was significantly reduced as a direct result of the increased interchain separation, leading to a higher value for the measured photoluminescence efficiency. Impedance spectroscopy showed an increase in permittivity, probably due to greater polarizability. Increases approaching one order of magnitude were observed for direct current hole conductivity and mobility values. Space charge limited conduction analysis suggests a narrowing of the highest occupied molecular orbital band tail on treatment resulting in reduced trapping. Single layer light emitting devices prepared using this technique were found to be significantly brighter and to have longer operating lifeti...
http://hdl.handle.net/2262/28386
Marcáilte
Marcáil
Electron-electron scattering in a double quantum dot: Effective mass approach
(2010)
PEROVA, TATIANA
Electron-electron scattering in a double quantum dot: Effective mass approach
(2010)
PEROVA, TATIANA
Achomaireacht:
We present a theoretical description of the first-order scattering of interacting electrons and holes in a double quantum dot. Assuming infinitely high walls, strong confinement, and a two-band approximation, we derive general expressions for the two-particle matrix elements of the screened Coulomb potential. We also determine the selection rules for different scattering channels and consider special cases where the corresponding matrix elements can be represented by simple analytical expressions. Numerical calculations of the matrix elements and an analysis of their dependence on the geometrical and material parameters of the double quantum dot have also been performed.
http://hdl.handle.net/2262/41172
Marcáilte
Marcáil
Thermally activated escape rate for a Brownian particle in a double-well potential for all values of the dissipation
(2006)
COFFEY, WILLIAM THOMAS; KALYMYKOV, YURI PETROVICH; TITOV, SERGEY
Thermally activated escape rate for a Brownian particle in a double-well potential for all values of the dissipation
(2006)
COFFEY, WILLIAM THOMAS; KALYMYKOV, YURI PETROVICH; TITOV, SERGEY
Achomaireacht:
peer-reviewed
The translational Brownian motion of a particle in a tilted washboard potential is considered. The dynamic structure factor and longest relaxation time are evaluated from the solution of the governing Langevin equation by using the matrix continued fraction method. The longest relaxation time is compared with the Kramers theory of the escape rate of a Brownian particle from a potential well as extended to the Kramers turnover region by Mel'nikov [Physics Reports 209, 1 (1991)]. It is shown that in the low temperature limit, the universal Mel'nikov expression for the escape rate provides a good estimate of the longest relaxation time for all values of dissipation including the very low damping (VLD), very high damping (VHD), and turnover regimes. For low barriers (where the Mel'nikov method is not applicable) and zero tilt, analytic equations for the relaxation times in the VLD and VHD limits are derived.
http://hdl.handle.net/2262/30552
Marcáilte
Marcáil
Estimation of asymmetry in physics
(1996)
WILSON, SIMON PAUL
Estimation of asymmetry in physics
(1996)
WILSON, SIMON PAUL
Achomaireacht:
peer-reviewed
The notion of asymmetry arises in many physical experiments, being a natural expression of the relative difference between two quantities. In this paper, we discuss the estimation of asymmetries between the rates of two event processes subject to a common background. Such asymmetries have many applications in solid-state physics - a measurement of the difference in arrival rates of elctrons with one of two possible spin orientations to a detector, for example. We describe three techniques for estimating asymmetries from observations subject to uncertainty: a naive method based on an unbiassed estimate and a Gaussian approximation, a bootstrap approach, and a Bayesian approach. Differences in the interpretation of the estimates are discussed and their performances are compared by means of a simulation study. The aim is both to review the methodology on estimation of asymmetries and to contribute to the more general discussion of the relative merits of frequentist an...
http://hdl.handle.net/2262/32969
Marcáilte
Marcáil
Conformal anomaly of (2,0) tensor multiplet in six dimensions and AdS/CFT correspondence
(2000)
FROLOV, SERGEY
Conformal anomaly of (2,0) tensor multiplet in six dimensions and AdS/CFT correspondence
(2000)
FROLOV, SERGEY
Achomaireacht:
We compute the conformal anomaly in the free d = 6 superconformal (2,0) tensor multiplet theory on generic curved background. Up to a trivial covariant totalderivative term, it is given by the sum of the type A part proportional to the 6-d Euler density, and the type B part containing three independent conformal invariants: two CCC contractions of Weyl tensors and a C?2C + ... term. Multiplied by the factor 4N3, the latter Weyl-invariant part of the anomaly reproduces exactly the corresponding part of the conformal anomaly of large N multiple M5-brane (2,0) theory as predicted (hep-th/9806087) by AdS7 supergravity on the basis of AdS/CFT correspondence. The coefficients of the type A anomaly differ by the factor 4 7 ? 4N3, so that the free tensor multiplet anomaly does not vanish on a Ricci-flat background. The coefficient 4N3 is the same as found (hep-th/9703040) in the comparison of the tensor multiplet theory and the d = 11 supergravity predictions for the absorption crosssection...
http://hdl.handle.net/2262/49076
Marcáilte
Marcáil
Tachyon condensation and universality of DBI action
(2001)
FROLOV, SERGEY
Tachyon condensation and universality of DBI action
(2001)
FROLOV, SERGEY
Achomaireacht:
We show that a low-energy action for massless fluctuations around a tachyonic soliton background representing a codimension one D-brane coincides with the Dirac-Born-Infeld action. The scalar modes which describe transverse oscillations of the D-brane are translational collective coordinates of the soliton. The appearance of the DBI action is a universal feature independent of details of a tachyon effective action, provided it has the structure implied by the open string sigma model partition function.
http://hdl.handle.net/2262/49328
Marcáilte
Marcáil
Application of statistical physics for the identification of important events in visual lifelogs
(2013)
Gurrin, Cathal; Ruskin, Heather J.; Crane, Martin; LI, Na
Application of statistical physics for the identification of important events in visual lifelogs
(2013)
Gurrin, Cathal; Ruskin, Heather J.; Crane, Martin; LI, Na
Achomaireacht:
Visual lifelogging is the process of automatically recording images and other sensor data. Microsoft’s SenseCam is lifelogging camera have mostly been used in medical applications. Experience shows that the SenseCam can be an effective memory aid device, as it helps users to improve recollecting an experience. Given the vast amount of images that are maintained in a visual lifelog, it is a significant challenge to deconstruct a sizeable collection of images into meaningful events for users. In this paper random matrix theory (RMT) is applied to a cross-correlation matrix C, constructed using SenseCam lifelog data streams to identify such events. The analysis reveals a number of eigenvalues that deviate from the spectrum suggested by RMT. The components of the deviating eigenvectors are found to correspond to “distinct significant events” in the visual lifelogs. Finally, the cross-correlation matrix is cleaned by separating the noisy part from non-noisy part of cross-correlation mat...
http://doras.dcu.ie/19944/
Marcáilte
Marcáil
What happens to the Υ and η b in the quark-gluon plasma? Bottomonium spectral functions from lattice QCD
(2011)
Aarts, Gert; Allton, Chris; Kim, Seyong; Lombardo, M. P.; Oktay, M. B.; Ryan, S. M.; Si...
What happens to the Υ and η b in the quark-gluon plasma? Bottomonium spectral functions from lattice QCD
(2011)
Aarts, Gert; Allton, Chris; Kim, Seyong; Lombardo, M. P.; Oktay, M. B.; Ryan, S. M.; Sinclair, D. K.; Skullerud, Jon-Ivar
Achomaireacht:
We study bottomonium spectral functions in the quark-gluon plasma in the Υ and η b channels, using lattice QCD simulations with two flavours of light quark on highly anisotropic lattices. The bottom quark is treated with nonr elativistic QCD (NRQCD). In the temperature range we consider, 0 . 42 ≤ T/T c ≤ 2 . 09, we find that the ground states survive, whereas the excited states are suppressed as the te mperature is increased. The position and width of the ground states are compared to analy tical effective field theory (EFT) predictions. Systematic uncertainties of the maximu m entropy method (MEM), used to construct the spectral functions, are discussed in s ome detail.
http://eprints.maynoothuniversity.ie/4825/
Marcáilte
Marcáil
Clebsch–Gordan and 6 j -coefficients for rank 2 quantum groups
(2010)
Ardonne, Eddy; Slingerland, J.K.
Clebsch–Gordan and 6 j -coefficients for rank 2 quantum groups
(2010)
Ardonne, Eddy; Slingerland, J.K.
Achomaireacht:
We calculate ( q -deformed) Clebsch–Gordan and 6 j -coefficients for rank 2 quantum groups. We explain in detail how such calculations are done, which should allow the reader to perform similar calculations in other cases. Moreover, we tabulate the q -Clebsch–Gordan and 6 j -coefficients explicitly, as well as some other topological data associated with theories corresponding to rank 2 quantum groups. Finally, we collect some useful properties of the fusion rules of particular conformal field theories.
http://eprints.maynoothuniversity.ie/4799/
Marcáilte
Marcáil
Kaleidoscope of topological phases with multiple Majorana species
(2011)
Kells, G.; Kailasvuori, J.; Slingerland, J.K.; Vala, J.
Kaleidoscope of topological phases with multiple Majorana species
(2011)
Kells, G.; Kailasvuori, J.; Slingerland, J.K.; Vala, J.
Achomaireacht:
Exactly solvable lattice models for spins and non-interacting fermions provide fascinating examples of topological phases, some of them exhibiting the localized Majorana fermions that feature in proposals for topological quantum computing. The Chern invariant ν is an important characterization of such phases. Here we look at the square–octagon variant of Kitaev’s honeycomb model. It maps to spinful paired fermions and enjoys a rich phase diagram featuring distinct Abelian and non-Abelian phases with ν = 0 , ± 1 , ± 2 , ± 3 and ± 4. The ν = ± 1 and ν = ± 3 phases all support localized Majorana modes and are examples of Ising and SU ( 2 ) 2 anyon theories, respectively
http://eprints.maynoothuniversity.ie/4798/
Marcáilte
Marcáil
Phase transitions in topological lattice models via topological symmetry breaking
(2012)
Burnell, F.J.; Simon, Steven H.; Slingerland, J.K.
Phase transitions in topological lattice models via topological symmetry breaking
(2012)
Burnell, F.J.; Simon, Steven H.; Slingerland, J.K.
Achomaireacht:
We study transitions between phases of matter with topological order. By studying these transitions in exactly solvable lattice models we show how universality classes may be identified and critical properties described. As a familiar example to elucidate our results concretely, we describe in detail a transition between a fully gapped achiral 2D p -wave superconductor ( p +i p for pseudo-spin up/ p − i p for pseudo-spin down) to an s-wave superconductor. We show in particular that this transition is of the 2D transverse field Ising universality class.
http://eprints.maynoothuniversity.ie/4796/
Marcáilte
Marcáil
Topological qubit design and leakage
(2011)
Ainsworth, R.; Slingerland, J.K.
Topological qubit design and leakage
(2011)
Ainsworth, R.; Slingerland, J.K.
Achomaireacht:
We examine how best to design qubits for use in topological quantum computation. These qubits are topological Hilbert spaces associated with small groups of anyons. Operations are performed on these by exchanging the anyons. One might argue that in order to have as many simple single-qubit operations as possible, the number of anyons per group should be maximized. However, we show that there is a maximal number of particles per qubit, namely 4, and more generally a maximal number of particles for qudits of dimension d . We also look at the possibility of having topological qubits for which one can perform two-qubit gates without leakage into non-computational states. It turns out that the requirement that all two-qubit gates are leakage free is very restrictive and this property can only be realized for two-qubit systems related to Ising-like anyon models, which do not allow for universal quantum computation by braiding. Our results follow directly from the representation theory of ...
http://eprints.maynoothuniversity.ie/4797/
Ag Taispeaint Torthaí 101 - 125 de 3195 ar leathanach 5 de 128
1
2
3
4
5
6
7
8
9
10
Bibtex
CSV
Fonóta
Obair Thagartha
RIS
XML
Cineál Míre
Book (3)
Book chapter (18)
Conference item (176)
Doctoral thesis (312)
Journal article (2462)
Master thesis (research) (66)
Master thesis (taught) (1)
Report (51)
Review (1)
Working paper (3)
Other (102)
Institiúid
Dublin City University (316)
NUI Galway (111)
Maynooth University (417)
Trinity College Dublin (1298)
University College Cork (350)
University College Dublin (98)
University of Limerick (49)
Dublin Institute of Technology (426)
Lenus (3)
Dundalk Institute of Techno... (28)
Marine Institute (5)
Royal College of Surgeons i... (94)
Stádas Athbhreithnithe Piaraí
Peer reviewed (2688)
Non peer reviewed (369)
Unknown (138)
Bliain
2017 (51)
2016 (198)
2015 (130)
2014 (220)
2013 (285)
2012 (265)
2011 (278)
2010 (285)
2009 (226)
2008 (164)
2007 (134)
2006 (120)
2005 (134)
2004 (92)
2003 (83)
2002 (68)
2001 (46)
2000 (63)
1999 (51)
1998 (43)
1997 (36)
1996 (35)
1995 (33)
1994 (32)
1993 (23)
built by Enovation Solutions