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All of these papers can be downloaded in Adobe Acrobat Reader format (.pdf). You can download this software here.

Using structural disorder to enhance the magnetism and spin-polarization in FexSi1-x thin films for spintronics J. Karel, Y. N. Zhang, C. Bordel, K. H. Stone, T. Y. Chen, C. A. Jenkins, David J. Smith, J Hu, R. Q. Wu, S. M. Heald, J. B. Kortright and F. Hellman, Materials Research Express 1, 026102 (2014) download

Effect of capping material on interfacial ferromagnetism in FeRh thin films C. Baldasseroni, G. K. Palsson, C. Bordel, S. Valencia, A. A. Unal, F. Kronast, S. Nemsak, C. S. Fadley, J. A. Borchers, B. B. Maranville, and F. Hellman, J. Appl. Phys. 115, 043919 (2014) download

Mean-field simulation of metal oxide antiferromagnetic films and multilayers M. Charilaou and F. Hellman, Phys. Rev. B 87, 184433 (2013) download

Excess Specific Heat in Evaporated Amorphous Silicon D. R. Queen, X. Liu, J. Karel, T. H. Metcalf, and F. Hellman, Phys. Rev. Lett. 110, 135901 (2013) download

Electron-Mediated Ferromagnetic Behavior in CoO/ZnO Multilayers. H.-J. Lee, C. Bordel, J. Karel, David W. Cooke, M. Charilaou, and F. Hellman, Phys. Rev. Lett. 110, 087206 (2013) download

Cr(110) texture induced by epitaxy on Al2O3(0001) substrates: Preferential grain growth in the <001> direction. Z. Boekelheide and F. Hellman, Appl. Phys. Lett. 102, 141601 (2013) download

Temperature-driven nucleation of ferromagnetic domains in FeRh thin films. C. Baldasseroni, C. Bordel, A. X. Gray, A. M. Kaiser, F. Kronast,J. Herrero-Albillos, C. M. Schneider, C. S. Fadley and F. Hellman, Appl. Phys. Lett. 100, 262401 (2012) download

Thermodynamic Measurements of Fe-Rh Alloys. David W. Cooke, F. Hellman, C. Baldasseroni, C. Bordel, S. Moyerman, and E. E. Fullerton, Phys. Rev. Lett. 109, 255901 (2012) download

Towards analysis of the electron density of states of Nb3Sn as a function of strain. M. G. T. Mentink, M. M. J. Dhalle, D. R. Dietderich, A. Godeke, W. Goldacker, F. Hellman,and H. H. J. ten Kate, AIP Conf. Proc. 1435, 225 (2012) download

Fe Spin Reorientation across the Metamagnetic Transition in Strained FeRh Thin Films. C. Bordel, J. Juraszek, David W. Cooke, C. Baldasseroni, S. Mankovsky, J. Minár, H. Ebert, S. Moyerman, E. E. Fullerton, and F. Hellman, Phys. Rev. Lett. 109, 117201 (2012) download

Effect of gadolinium adatoms on the transport properties of graphene. M. Alemani, A. Barfuss, B. Geng, C. Girit, P. Reisenauer, M. F. Crommie, F. Wang, A. Zettl, and F. Hellman, Phys. Rev. B 85, 094413 (2012) download

Electronic Structure Changes across the Metamagnetic Transition in FeRh via Hard X-Ray Photoemission. A. X. Gray, D. W. Cooke, P. Krüger, C. Bordel, A. M. Kaiser, S. Moyerman, E. E. Fullerton, S. Ueda, Y. Yamashita, A. Gloskovskii, C. M. Schneider, W. Drube, K. Kobayashi, F. Hellman, and C. S. Fadley, Phys. Rev. Lett. 108, 257208 (2012) download

Chemical ordering in Cr3Al and relation to semiconducting behavior. Z. Boekelheide, D. A. Stewart, and F. Hellman, Phys. Rev. B 86, 085120 (2012) download

Antiferromagnetism in Cr3Al and relation to semiconducting behavior. Z. Boekelheide, T. Saerbeck, Anton P. J. Stampfl, R. A. Robinson, D. A. Stewart, and F. Hellman, Phys. Rev. B 85, 094413 (2012) download

Heat transfer simulation and thermal measurements of microfabricated x-ray transparent heater stages. C. Baldasseroni, D. R. Queen, David W. Cooke, K. Maize, A. Shakouri, and F. Hellman, Rev. Sci. Instrum. 82, 093904 (2011) download

Hard x-ray photoemission study of near-Heusler FexSi1-x alloys. A. X. Gray, J. Karel, J. Minar, C. Bordel, H. Ebert, J. Braun, S. Ueda, Y. Yamashita, L. Ouyang, D. J. Smith, K. Kobayashi, F. Hellman, and C. S. Fadley, Phys. Rev. B, 83, 195112, (2011) download

Calorimetry of epitaxial thin films. David W. Cooke, F. Hellman, J. R. Groves, B. M. Clemens, S. Moyerman, and E. E. Fullerton, Rev. Sci. Instrum. (2011) download

Band gap and electronic structure of an epitaxial, semiconducting Cr0.80Al0.20 thin film. Z. Boekelheide, A. X. Gray, C. Papp, B. Balke, D. A. Stewart, S. Ueda, K. Kobayashi, F. Hellman, and C. S. Fadley, Phys. Rev. Lett. 105, 236404, (2010) download

Effect of magnetic Gd adatoms on the transport properties of ultrathin gold films. M. Alemani, A. Huegel, E. Helgren, D. R. Queen, and F. Hellman, Phys. Rev. B 82, 195447, (2010) download

Distinct local electronic structure and magnetism for Mn in amorphous Si and Ge. Li Zeng, J. X. Cao, E. Helgren, J. Karel, E. Arenholz, Lu Ouyang, David J. Smith, R. Q. Wu, and F. Hellman, Phys. Rev. B 82, 165202, (2010) download

Evidence for nanoscale two-dimensional Co clusters in CoPt3 films with perpendicular magnetic anisotropy. J. O. Cross, M Newville, B B Maranville, C Bordel, F Hellman and V G Harris, J. Phys.: Condens. Matter 22, 146002, (2010) download

Resonant impurity scattering and electron-phonon scattering in the electrical resistivity of Cr thin films. Z. Boekelheide, David W. Cooke, E. Helgren, and F. Hellman, Phys. Rev. B 80, 134426, (2009) download

Electronic and vibrational density of states through the metal-insulator transition in amorphous yttrium-silicon alloy thin films. B.L. Zink and F. Hellman, Phys. Rev. B 79, 235105, (2009)  download

Tracking spin-glass barriers versus field and temperature in a-Gd0.19Si0.81. V. Orlyanchik, M.B. Weissman, E. Helgren, L. Zeng, and F. Hellman, Phys. Rev. B 79, 224402 (2009) download

Gate-controlled magnetic properties of the magnetic semiconductor (Zn,Co)O. H.-J. Lee, E. Helgren, and F. Hellman, Applied Physics Letters 94, 212106 (2009) download

Thin film nanocalorimeter for heat capacity measurements of 30 nm films. D.R. Queen and F. Hellman, Review of Scientific Instruments 80, 063901 (2009): selected for the June 15, 2009 issue of Virtual Journal of Nanoscale Science & Technology. download

The role of the spin-density wave and disorder in the density of states of sputtered Cr films. David W.Cooke, Z. Boelkelheide, D.R. Queen, and F. Hellman, J. Appl. Phys. 105, 07C314 (2009) download

Thermodynamic measurements of submilligram bulk samples using a membrane-based 'calorimeter on a chip'. D.W. Cooke, K.J. Michel, and F. Hellman, Review of Scientific Instruments 79, 053902 (2008). download

X-ray adsorption study of the electronic structure of Mn-doped amorphous Si. Li Zeng, A. Huegel, E. Helgren, F. Hellman, C. Piamonteze, and E. Arenholz, Appl. Phys. Lett. 92, 142503 (2008)

Quenched magnetic moment in Mn-doped amorphous Si films. Li Zeng, E. Helgren, M. Rahimi, F. Hellman, R. Islam, B.J. Wilkens, R.J. Culbertson and D. Smith, Phys. Rev. B 77, 073306 (2008) download

Spin-density wave in polycrystalline Cr films from infrared reflectivity. Z. Boekelheide, E. Helgren, F. Hellman, Phys. Rev. B, 76, 224429 (2007) download

Magnetic and transport properties of amorphous GdxGe1−x alloys near the metal-insulator transition.  E. Helgren, F. Hellman, Li Zeng, N. Sinenian, R. Islam, and David J. Smith, Phys. Rev. B 76, 184440 (2007) download

Microstructure, magnetotransport, and magnetic properties of Gd-doped amorphous carbon. Li Zeng, E. Helgren, F. Hellman, R. Islam, D. J. Smith, J. W. Ager, III, Phys. Rev. B, 75, 235450 (2007) download

Application of calorimetry on a chip to high-pressure materials. Alexandra Navrotsky, Maria Dorogova, Frances Hellman, David W. Cooke, Barry L. Zink, Charles E. Lesher, Juliana Boerio-Goates, Brian F. Woodfield, Brian Lang, PNAS 104:22, 9187 (2007) download

Concentration dependent microstructure and transport properties of the magnetic semiconductor Gd-Si. E. Helgren, D. R. Queen, F. Hellman, L. Zeng, R. Islam, David J. Smith, J. Appl. Phys., 101, 093712 (2007) download

Growth and microstructure dependence of electronic and magnetic properties in magnetically doped Gd-Si amorphous semiconductors. L. Zeng, E. Helgren, R. Islam, David J. Smith, F. Hellman, Phys. Rev. B, 75, 184404 (2007) download

Effects of annealing on amorphous GdxSi1-x near the metal-insulator transition. E. Guillotel, L. Zeng, E. Helgren, F. Hellman, R. Islam, David J. Smith, J. Appl. Phys., 101, 023908 (2007) download

Excess modes and enhanced scattering in rare-earth-doped amorphous silicon thin films. B. L. Zink, R. Islam, David J. Smith, F. Hellman, Phys. Rev. B 74, 205209 (2006). download

Thermal conductivity and specific heat of thin-film amorphous silicon. B. L. Zink, R. Pietri, and F. Hellman, Phys. Rev. Lett., 96, 055902 (2006) download

Simulation of clustering and anisotropy due to Co step-edge segregation in vapor deposited CoPt3. B. B. Maranville, M. Schuerman, and F. Hellman, Phys. Rev. B, 73, 104435 (2006) download

Field- and concentration-tuned scaling of a quantum phase transition in a magnetically doped semiconductor. E. Helgren, L. Zeng, K. Burch, D. Basov, and F. Hellman, Phys. Rev. B, 73, 155201 (2006) download

Magnetic rare earth (Gd) implanted tetrahedral amorphous carbon (ta-C). L. Zeng, E. Helgren, H. Zutz, C. Ronning, F. Hellman, Mater. Res. Soc. Symp. Proc. 941, Q08-22 (2006). download

Prototype of a radiation hard resistive bolometer for ITER. L. Giannone, D. R. Queen, F. Hellman, and J. C. Fuchs, Plasma Phys. Control. Fusion 47, 2123-2143 (2005). download

Beneficial effects of annealing on amorphous Nb-Si thin film thermometers. D. Querlioz, E. Helgren, D. R. Queen, F. Hellman, R. Islam, David J. Smith, Appl. Phys. Lett. 87, 221901 (2005). download

Si-N membrane-based microcalorimetry: Heat capacity and thermal conductivity of thin films. B. Revaz, B.L. Zink and F. Hellman, Thermochimica Acta 432 (2005) 158¨C168 download

Measurement of Thermal Conductivity of Thin Films with a Micromachined Membrane Calorimeter. B. L. Zink, B. Revaz, J. J. Cherry, and F. Hellman, Rev. Sci. Instr. 76, 24901-5 (2005). download

Characteristic temperature in magnetically-doped amorphous semiconductors. E. Helgren, J. Cherry, L. Zeng, F. Hellman, Phys. Rev. B 71, 113203 (2005). download

Interplay between charge localization and magnetic ordering in amorphous GdxSi1-x. N. K. Chumakov, S. V. Gudenko, V. V. Tugushev, A. B. Davydov, V. I. Ozhogin, E. Helgren, and F. Hellman, J. Magn. Magn. Mat., 272-276, 1351-2 (2004). download

Variation of the density of states in amorphous GdSi at the metal-insulator transition. L. Bokacheva, W. Teizer, F. Hellman, and R. C. Dynes, Phys. Rev. B 69, 235111 (2004). download

Specific Heat and Thermal Conductivity of Low-Stress Amorphous Si-N Membranes. B. L. Zink and F. Hellman, Sol. St. Comm. 129, (2004). download

AFM Excitations in the Specific Heat of La2CuO4.11 Single Crystals. G. A. Jorge, M. Jaime, L. Civale, C. Batista, B. L. Zink, F. Hellman, B. Khaykovich, M. A. Kastner, Y. S. Lee, and R. J. Birgeneau, Phys Rev B 69, 174506 (2004). download

Numerical Simulation of the Heat Transfer in a-Si-N-Membrane Based Microcalorimeters. B. Revaz, D. O'Neil, L. Hull, and F. Hellman, Rev. Sci. Instr. 74, 4389 (2003). download

Spin Polarized Tunneling at the Metal-Insulator Transition. W. Teizer, F. Hellman and R. C. Dynes, Int'l J. of Mod. Physics B, Vol. 0, 1-3, 2003. download

XAFS Study of Local Disorder in a-GdxSi1-x Amorphous Magnetic Semiconductor. D. Haskel, J. W. Freeland, J. Cross, R. Winarski, M. Newville, and F. Hellman, Phys. Rev. B 67, 115207 (2003) . download

Mean Field Behavior with Gaussian Fluctuations at the Ferromagnetic Phase Transition of SrRuO3. D. Kim, B. L. Zink, F. Hellman, S. McCall, G. Cao, and J. E. Crow, Phys. Rev. B Rapid Communications 67, 100406 (2003) . download

Flux Pinning Enhancement in Ferromagnetic and Superconducting Thin Film Multilayer. D.B. Jan, J.Y. Coulter, B.B. Maranville, M.E. Hawley, L.N. Bulaevskii, M.P. Maley, F. Hellman, X.Q. Pan, and Q.X. Jia, Appl. Phys. Lett. 82, 778 (2003). download

The Hall Effect at a Tunable Metal-Insulator Transition. W. Teizer, F. Hellman, and R.C. Dynes, Phys. Rev. B Rapid Communications 67, 121102 (2003) download

Finite Size Effects on the Moment and Ordering Temperatures in Antiferromagnetic CoO Layers. Y. J. Tang, D. J. Smith, B. L. Zink, F. Hellman, and A. E. Berkowitz, Phys. Rev. B. 67, 054408 (2003). download

Magnetic and Transport Properties of Amorphous Tb-Si Alloys Near the Metal-Insulator Transition. M. Liu and F. Hellman, Phys. Rev. B. 67, 054401 (2003). download

High Field Magneto-Optic Measurements of Amorphous Gd-Si Alloys. F. Hellman, W. Geerts and B. Donehew, Phys. Rev. B. 67, 012406 (2003). download

Structural and Magnetic Length Scales in Amorphous TbFe2. T. C. Hufnagel and F. Hellman, J. Magn. Magn. Mat. 256/1-3, 322 (2003). download

Magnetic Moments and Interactions Near the Metal-Insulator Transition in Amorphous Magnetic Semiconductors. B. L. Zink, V. Preisler, D. R. Queen, and F. Hellman, Phys. Rev. B 66, 19528 (2002). download

Oxygen-Assisted Room-Temperature Deposition of CoPt3 Films with Perpendicular Magnetic Anisotropy. B. B. Maranville and F. Hellman, Appl. Phys. Lett. 81, 4011-13 (2002). download

Tricritical Point and the Doping Dependence of the Order of the Ferromagnetic Phase Transition of La1-xCaxMnO3. D. Kim, B. Revaz, B. L. Zink, F. Hellman, J. F. Mitchell and J. J. Rhyne, Phys. Rev. Lett. 89, 7202-06 (2002). download

Enhancement of the electronic contribution to the low temperature specific heat of an Fe/Cr magnetic multilayer. B. Revaz, M.-C. Cyrille, B. Zink, I. K. Schuller and F. Hellman, Phys. Rev. B 65, 944171 (2002). download

Thin Film Microcalorimeter for Heat Capacity Measurements in High Magnetic Fields. B. L. Zink, B. Revaz, R. Sappey, F. Hellman, Rev. Sci. Instr. 73, 1841 (2002). download

Infrared probe of metal-insulator transition in Si1-xGdx and Si1-xYx amorphous alloys in magnetic field. D. N. Basov, A. M. Bratkovsky, P. F. Henning, B. Zink, F. Hellman, C. C. Homes, and M. Strongin, Europhys. Lett. 57, 240-6 (2002). download

Critical properties of La1-xSrxMnO3. D. Kim, F. Hellman, and J. M. D. Coey, Phys. Rev. B 65, 214424 (2002). download

Miscut-angle dependence of perpendicular magnetic anisotropy in thin epitaxial CoPt3 films grown on vicinal MgO. B. B. Maranville, A. L. Shapiro,  F. Hellman, D. M. Schaadt and E. T. Yu, Appl. Phys. Lett. 81, 517 (2002). (download)

Thin film microcalorimeter for measurement of specific heat in high magnetic fields. B. L. Zink, B. Revaz, R. Sappey and F. Hellman, Rev. Sci. Instrum. 73, 1841 (2002). (download)

Magnetic Anisotropy in Films.  F. Hellman, article in the Encyclopedia of Materials: Science and Technology, Elsevier (in press).

Enhancement of the electronic contribution to the low temperature specific heat of Fe/Cr magnetic multilayer. B. Revaz, M.-C. Cyrille, B. L. Zink, I. K. Schuller and F. Hellman, Phys. Rev. B 65, 094417 (2002). (download)

Ion-beam assisted growth of perpendicular anisotropy materials. D. Vasumathi, B. M. Maranville, and F. Hellman, Appl. Phys. Lett. 79, 2782 (2001). (download)

Growth-induced perpendicular magnetic anisotropy and clustering in NixPt1-xalloys. D. Vasumathi, A. L. Shapiro, B. B. Maranville, and F. Hellman J. Magn. Magn. Mat. 223, 221 (2001). (download)

The Density of States of Amorphous GdxSi1-x at the Metal-Insulator Transition. W. Teizer, F. Hellman, and R. C. Dynes, Phys. Rev. Lett. 85, 848 (2000). (download)

Spin Glass Freezing and RKKY Interactions Near the Metal-Insulator Transition in Amorphous Gd-Si Alloys. F. Hellman, D. R. Queen, R. M. Potok, and B. L. Zink, Phys. Rev. Lett. 84, 5411 (2000). (download)

Magnetic Field Induced Insulator-Metal Transition in a-GdxSi1-x. W. Teizer, F. Hellman, and R. C. Dynes, Solid State Communications 114, 81 (2000). (download)

Growth-Induced Magnetic Anisotropy and Clustering in Vapor-Deposited Co-Pt Alloy Films.  A. L. Shapiro, P.W. Rooney, M. Q. Tran, F. Hellman, K. M. Ring, K. L. Kavanagh, B. Rellinghaus, and D.Weller,  Phys Rev. B 60, R12826 (1999) (download)

Suppression of growth-induced perpendicular magnetic anisotropy in Co-Pt alloys by trace amounts of Si. A. L. Shapiro, O. Vajk, B. M. Maranville, and F. Hellman,Appl. Phys. Lett. 75, 4177 (1999). (download)

Large Magnetic Entropy in Giant Magnetoresistive Amorphous Gadolinium Silicon. B. L. Zink, E. Janod, K. Allen, F. Hellman,Phys. Rev. Lett. 83, 2266 (1999) (download)

Specific Heat of Endohedral and Higher Fullerene Thin Films. K. Allen, F. Hellman, Journal of Chemical Physics, vol.111, (no.12), AIP, 22 Sept. 1999. p.5291-4 (download)

Specific Heat of C60 and K3C60 Thin Films, 6-400 K. K. Allen, F. Hellman, Phys Rev. B 60, R11765 (1999) (download)

Long Ferromagnetic Correlation Length in Amorphous TbFe2. F. Hellman, A. L. Shapiro, E. N. Abarra, R. A. Robinson, R. P. Hjelm, P.A. Seeger, J. J. Rhyne, and J. I. Suzuki, Phys. Rev. B 59, 11408 (1999) (download)

Low temperature Magnetoresistance in Insulating a-Si:Gd Alloys. P. Xiong, B. L. Zink, S. I. Applebaum, F. Hellman, and R. C. Dynes, Phys. Rev. B 59, R3929 (1999) (download)

Coercivity in Amorphous Tb-Fe alloys. F. Hellman, M. Messer, and E. N. Abarra, J. Appl. Phys. 86, 1047(1999). (download)

Specific heat of amorphous rare-earth-transition-metal films. F. Hellman, E. N. Abarra, A. L. Shapiro, R. B. van Dover, Phys. Rev. B 58, 5672 (1998) (download)

Destruction of Superconductivity in the Narrow-band Metal,  K3C60 . Susan Watson, Kimberly Allen, D. W. Denlinger, and F. Hellman, Phys. Rev. B 55, 3866 (1997). (abstract) , (download)

Metal-Insulator Transition and Giant Negative Magnetoresistance in Amorphous Magnetic Rare Earth Silicon Alloys. F. Hellman, M. Q. Tran, A. E. Gebala, E. M. Wilcox, and R. C. Dynes, Phys. Rev. Lett. 22, 4652 (1996). (abstract) , (download)

Thermodynamic Measurements of Magnetic Ordering in Antiferromagnetic Superlattices. E. N. Abarra, K. Takano, A. E. Berkowitz, and F. Hellman, Phys Rev Lett 77, 3451 (1996). (download)

Evidence of a Surface-Mediated Magnetically-Induced Miscibility Gap in Co-Pt Alloy Thin Films. P.W. Rooney, A. L. Shapiro, M. Q. Tran, and F. Hellman, Phys. Rev. Lett. 75, 1843 (1995). (download)

Thin Film Microcalorimeter for Heat Capacity Measurements from 1.5 to 800 K. D. W. Denlinger, E. N. Abarra, Kimberly Allen, P. W. Rooney, S. K. Watson, and F. Hellman , Rev. Sci. Instrum. 65, 946 (1994). (abstract) (download)

Surface-induced Ordering: A Model for Vapor-deposition Growth of Amorphous Materials. F. Hellman, Appl. Phys. Lett. 64, 1947 (1994). (download)