D. Graf

Details der Publikationsliste

Zeitraum

1990 - 2010

Anzahl

56

Co-Autoren

Phase diagram of magnetic-field-induced superconductor O-(BETS)2FeCl4-xBrx (2010)

S. Uji, S. Yasuzuka, H. Tanaka, M. Tokumoto, B. Zhang, H. Kobayashi, ...

Abstract. Resistance measurements of λ-(BETS) 2FeCl 4-xBr x (x=0.7) have been performed to investigate the high magnetic field electronic state. When the magnetic field is applied exactly parallel...

DOI: 10.1051/jp4:2004114079 (2010)

K. Murata, T. Nakanishi, H. Yoshino, T. Konoike, J. Brooks, D. Graf, ...

Possible quantum hall effect in the two-dimensional organic conductor, W-(EDO-S, S-DMEDT-TTF)2(AuBr2)1+y in the two-Fermi surface system

(M=Ga, Fe) (2010)

Edp Sciences, Les Ulis, E. S. Choi, D. Graf, J. S. Brooks, J. Yamada, ...

The pressure-temperature phase diagram of pressure induced organic superconductors E-(BDA-TTP)2MCl4

High resolution miniature dilatometer based on AFM piezocantilever (2009)

Park, J. -H., Graf, D., Murphy, T. P., Schmiedeshoff, G. M., Tozer, S. W.

Thermal expansion, or dilation, is closely related to the specific heat, and provides useful information regarding material properties. The accurate measurement of dilation in confined spaces coupled...

Geometrical and orbital effects in a quasi-one dimensional conductor (2009)

Graf, D., Brooks, J. S., Choi, E. S., Almeida, M., Henriques, R. T., Dias, J. C., ...

The angular dependent magnetoresistance of (Per)2[Au(mnt)2] under pressure has revealed geometrical effects associated with the crystallographic parameters. Pressure suppresses the charge density...

Role of anion size, magnetic moment, and disorder on the properties of the organic conductor kappa-(BETS)_2Ga_{1-x}Fe_{x}Cl_{4-y}_Br_{y} (2009)

Steven, E., Cui, H. B., Kismarahardja, A., Brooks, J. S., Graf, D., Kobayashi, H.

Shubnikov-de Haas and angular dependent magnetoresistance oscillations have been used to explore the role of anion size, magnetic moment, and disorder in the organic conductors kappa-(BETS)_2GaBr_{4}...

Fermi Surface of Alpha-Uranium at Ambient Pressure (2009)

Graf, D., Stillwell, R., Murphy, T. P., Park, J. -H., Kano, M., Palm, E. C., ...

We have performed de Haas-van Alphen measurements of the Fermi surface of alpha-uranium single crystals at ambient pressure within the alpha-3 charge density wave (CDW) state from 0.020 K - 10 K and...

Anisotropy of the upper critical field in a Co-doped BaFe2As2 single crystal (2009)

Kano, M., Kohama, Y., Graf, D., Balakirev, F. F., Sefat, A. S., McGuire, M. A., ...

The temperature dependence of the upper critical magnetic field (Hc2) in a BaFe1.84Co0.16As2 single crystal was determined via resistivity, for the inter-plane (H^ab) and in-plane (H//ab) directions...

Pressure Evolution of a Field Induced Fermi Surface Reconstruction and of the Neel Critical Field in CeIn3 (2009)

Purcell, K. M., Graf, D., Kano, M., Bourg, J., Palm, E. C., Murphy, T., ...

We report high-pressure skin depth measurements on the heavy fermion material CeIn3 in magnetic fields up to 64 T using a self-resonant tank circuit based on a tunnel diode oscillator. At ambient...

ABSTRACTS (2009)

Abdelwahab, A., Gardner, M., Parkash, R., Basta, M., Sapp, J., Veltmann, C., ...

Introduction: Scar-related ventricular tachycardia (VT) is often unmappable. Data regarding the outcomes of ablation for mappable vs unmappable VT are lacking. Methods: Catheter ablation of...

Coulomb oscillations in three-layer graphene nanostructures (2008)

Guettinger, J., Stampfer, C., Molitor, F., Graf, D., Ihn, T., Ensslin, K.

We present transport measurements on a tunable three-layer graphene single electron transistor (SET). The device consists of an etched three-layer graphene flake with two narrow constrictions...

High magnetic field-induced insulating phase in an organic conductor (2008)

Brooks, J.S., Graf, D., Choi, E.S., Storr, K., Mielke, C.H., Papavassiliou, George C., ...

The full text is available at: http://arxiv.org/PS_cache/cond-mat/pdf/0209/0209592v1.pdf

Raman imaging of doping domains in graphene on SiO2 (2007)

Stampfer, C., Wirtz, L., Jungen, A., Graf, D., Molitor, F., Hierold, C., ...

We present spatially resolved Raman images of the G and 2D lines of single-layer graphene flakes. The spatial fluctuations of G and 2D lines are correlated and are thus shown to be affiliated with...

Tunable Coulomb blockade in nanostructured graphene (2007)

Stampfer, C., Guettinger, J., Molitor, F., Graf, D., Ihn, T., Ensslin, K.

We report on Coulomb blockade and Coulomb diamond measurements on an etched, tunable single-layer graphene quantum dot. The device consisting of a graphene island connected via two narrow graphene...

Raman imaging and electronic properties of graphene (2007)

Molitor, F., Graf, D., Stampfer, C., Ihn, T., Ensslin, K.

Graphite is a well-studied material with known electronic and optical properties. Graphene, on the other hand, which is just one layer of carbon atoms arranged in a hexagonal lattice, has been...

Local gating of a graphene Hall bar by graphene side gates (2007)

Molitor, F., Güttinger, J., Stampfer, C., Graf, D., Ihn, T., Ensslin, K.

We have investigated the magnetotransport properties of a single-layer graphene Hall bar with additional graphene side gates. The side gating in the absence of a magnetic field can be modeled by...

Phase coherent transport in a side-gated mesoscopic graphite wire (2007)

Graf, D., Molitor, F., Ihn, T., Ensslin, K.

We investigate the magnetotransport properties of a thin graphite wire resting on a silicon oxide substrate. The electric field effect is demonstrated with back and side gate electrodes. We study the...

IKOPA - Kulturwandel in klein- und mittelständischen Unternehmen (2007)

Schallock, B., Graf, D.

Generally, small companies regard management concepts very critically. Changes have to promise tangible profit and must be easily integrable into everyday business. Fraunhofer IPK is meeting these...

Spatially Resolved Raman Spectroscopy of Single- and Few-Layer Graphene (2006)

Graf, D., Molitor, F., Ensslin, K., Stampfer, C., Jungen, A., Hierold, C., ...

We present Raman spectroscopy measurements on single- and few-layer graphene flakes. Using a scanning confocal approach we collect spectral data with spatial resolution, which allows us to directly...

Local oxidation of Ga[Al]As heterostructures with modulated tip-sample voltages (2006)

Graf, D., Frommenwiler, M., Studerus, P., Ihn, T., Ensslin, K., Driscoll, D. C., ...

Nanolithography based on local oxidation with a scanning force microscope has been performed on an undoped GaAs wafer and a Ga[Al]As heterostructure with an undoped GaAs cap layer and a shallow...

Magnetic Field Dependence of CDW Phases in Per2M(mnt)2 (M=Pt, Au) (2005)

Brooks, J. S., Graf, D., Choi, E. S., Almeida, M., Dias, J. C., Henriques, R. T., ...

Recently the authors discovered that the suppression of the charge density wave (CDW) ground states by high magnetic fields in the organic conductor series Per2M(mnt)2 is followed by additional high...

Magnetic Field Dependent Behavior of the CDW ground state in Per2M(mnt)2 (M = Au, Pt) (2005)

Brooks, J. S., Graf, D., Choi, E. S., Almeida, M., Dias, J. C., Henriques, R. T., ...

The Per2M(mnt)2 class of organic conductors exhibit a charge density wave (CDW) ground state below about 12 K, which may be suppressed in magnetic fields of order 20 to 30 T. However, for both cases...

Magnetization, thermoelectric, and pressure studies of the magnetic field-induced metal to insulator transition in tau phase organic conductors (2004)

Graf, D., Choi, E. S., Brooks, J. S., Harrison, N., Murata, K., Konoike, T., ...

We have investigated the magnetic field-induced metal-insulator transition in the tau-phase organic conductors, which occurs in fields above 35 T, and below 14 K, by magnetization, thermoelectric,...

Multi-terminal transport through a quantum dot in the Coulomb blockade regime (2004)

Leturcq, R., Graf, D., Ihn, T., Ensslin, K., Driscoll, D. D., Gossard, A. C.

Three terminal tunnelling experiments on quantum dots in the Coulomb blockade regime allow a quantitative determination of the coupling strength of individual quantum states to the leads. Exploiting...

High magnetic field induced charge density wave states in a quasi-one dimensional organic conductor (2003)

Graf, D., Choi, E. S., Brooks, J. S., Henriques, Rui T., Almeida, M., Matos, M.

We have measured the high field magnetoresistence and magnetization of quasi-one- dimensional (Q1D) organic conductor (Per)2Pt(mnt)2 (where Per = perylene and mnt = maleonitriledithiolate), which has...

Suppression of a charge density wave ground state in high magnetic fields: spin and orbital mechanisms (2003)

Graf, D., Brooks, J. S., Choi, E. S., Uji, S., Dias, J. C., Almeida, M., ...

The charge density wave (CDW) transition temperature in the quasi-one dimensional (Q1D) organic material of (Per)$_2$Au(mnt)$_2$ is relatively low (TCDW = 12 K). Hence in a mean field BCS model, the...

High magnetic field-induced insulating phase in an organic conductor (2002)

Brooks, J. S., Graf, D., Choi, E. S., Balicas, L., Storr, K., Mielke, C. H., ...

We report electrical transport, skin depth, and magnetocaloric measurements in the tau-series of organic conductors at very high magnetic fields. Above 36 T these materials show a magnetic field...

Disorder-driven magnetic field-dependent phases in an organic conductor (2002)

Storr, K., Graf, D., Brooks, J. S., Balicas, L., Mielke, C., Papavassiliou, G. C.

We report inter-plane ($R_{zz}$) electrical transport measurements in the \tp series of organic conductors at very high magnetic fields. In the field range between 36 and 60 T $R_{zz}$ shows a very...

Magnetic field-dependent interplay between incoherent and Fermi liquid transport mechanisms in low-dimensional tau phase organic conductors (2000)

Storr, K., Balicas, L., Brooks, J. S., Graf, D., Papavassiliou, G. C.

We present an electrical transport study of the 2-dimensional (2D) organic conductor tau-(P-(S,S)-DMEDT-TTF)_2(AuBr)_2(AuBr_2)_y (y = 0.75) at low temperatures and high magnetic fields. The...

Shubnikov-de Haas effect and Yamaji oscillations in the antiferromagnetically ordered organic superconductor k-(BETS)2FeBr4: A Fermiology study (2000)

Balicas, L., Brooks, J. S., Storr, K., Graf, D., Uji, S., Shinagawa, H., ...

Shubnikov-De Haas effect (SdH) effect and angular dependent magnetoresistance oscillations (AMRO) were observed in the organic superconductor: $\kappa$-(BETS)$_2$FeBr$_4$. In contrast to its...

Phosphoinositide 3-kinase-dependent Ras activation by tauroursodesoxycholate in rat liver (2000)

Kurz, AK ; JFA; CORA, Block, Chantal; U0046116 ;, Graf, D, Vom Dahl, S, Schliess, F, Haussinger, D

Ursodesoxycholic acid, widely used for the treatment of cholestatic liver disease, causes choleretic, anti-apoptotic and immunomodulatory effects. Here the effects on choleresis of its taurine...

Rational primer design greatly improves differential display-PCR (DD-PCR).

Graf, D, Fisher, A G, Merkenschlager, M

Since its conception in 1992, differential display PCR (DD-PCR) has attracted widespread interest. Theoretically an attractive cloning approach, it combines the comparative analysis of several...

Phosphoinositide 3-kinase-dependent Ras activation by tauroursodesoxycholate in rat liver.

Kurz, A K, Block, C, Graf, D, Dahl, S V, Schliess, F, Häussinger, D

Ursodesoxycholic acid, widely used for the treatment of cholestatic liver disease, causes choleretic, anti-apoptotic and immunomodulatory effects. Here the effects on choleresis of its taurine...

Rational primer design greatly improves differential display-PCR (DD-PCR).

Graf, D, Fisher, A G, Merkenschlager, M

Since its conception in 1992, differential display PCR (DD-PCR) has attracted widespread interest. Theoretically an attractive cloning approach, it combines the comparative analysis of several...

Phosphoinositide 3-kinase-dependent Ras activation by tauroursodesoxycholate in rat liver.

Kurz, A K, Block, C, Graf, D, Dahl, S V, Schliess, F, Häussinger, D

Ursodesoxycholic acid, widely used for the treatment of cholestatic liver disease, causes choleretic, anti-apoptotic and immunomodulatory effects. Here the effects on choleresis of its taurine...