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Related papers: Tracking defect-induced ferromagnetism in GaN:Gd

200 papers

We investigated the origin of ferromagnetism in epitaxially grown Mn-doped Ge thin films. Using low-temperature molecular beam epitaxy, Mn-doped Ge films were successfully grown without precipitation of ferromagnetic Ge-Mn intermetallic…

Materials Science · Physics 2009-11-11 Satoshi Sugahara , Kok Leong Lee , Shinsuke Yada , Masaaki Tanaka

Present work investigates the structural, electronic and magnetic properties of wurtzite (0001) GaN nanowires (NWs) doped with Gd and point defects by employing the GGA+U approximation. We find that Ga vacancies (VGa) exhibit lower…

Materials Science · Physics 2015-11-09 Assa Aravindh S , Iman S Roqan

We report on the fabrication of pseudomorphic wurtzite GaMnN grown on GaN with Mn concentrations up to 10% using molecular beam epitaxy. According to Rutherford backscattering the Mn ions are mainly at the Ga-substitutional positions, and…

N-type doping of GaAs nanowires has proven to be difficult because the amphoteric character of silicon impurities is enhanced by the nanowire growth mechanism and growth conditions. The controllable growth of n-type GaAs nanowires with…

A range of high quality Ga1-xMnxN layers have been grown by molecular beam epitaxy with manganese concentration 0.2 < x < 10%, having the x value tuned by changing the growth temperature (Tg) between 700 and 590 {\deg}C, respectively. We…

We present a detailed study of the magnetic properties of low-temperature-molecular-beam-epitaxy grown Ge:Mn dilute magnetic semiconductor films. We find strong indications for a frozen state of Ge_{1-x}Mn_{x}, with freezing temperatures of…

Materials Science · Physics 2007-05-23 C. Jaeger , C. Bihler , T. Vallaitis , S. T. B. Goennenwein , M. Opel , R. Gross , M. S. Brandt

Mn-doped GaAs thin films were grown at a high substrate temperature of 580 C. During the growth process, the Mn cell temperature was ramped at different rates, resulting in a variety of different Mn concentration depth profile slopes, as…

Mesoscale and Nanoscale Physics · Physics 2015-02-11 P. Xu , D. Qi , M. L. Ackerman , S. D. Barber , P. M. Thibado

Mn doped GaAs thin films were grown using molecular beam epitaxy at high and low substrate temperatures. The elemental concentration depth profiles in the thin films were determined by using Auger electron spectroscopy combined with ion…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 J. F. Xu , P. M. Thibado , C. Awo-Affouda , R. Moore , V. P. LaBella

Following the theoretical predictions of ferromagnetism in Mn- and Co-doped ZnO, several workers reported ferromagnetism in thin films as well as in bulk samples of these materials. While some observe room-temperature ferromagnetism, others…

Materials Science · Physics 2007-05-23 C. N. R. Rao , F. L. Deepak

We examine the Mn concentration dependence of the electronic and magnetic properties of optimally annealed Ga1-xMnxAs epilayers for 1.35% < x < 8.3%. The Curie temperature (Tc), conductivity, and exchange energy increase with Mn…

Condensed Matter · Physics 2009-11-07 S. J. Potashnik , K. C. Ku , R. Mahendiran , S. H. Chun , R. F. Wang , N. Samarth , P. Schiffer

We have conducted a detailed thin film growth structure of oxygen engineered monoclinic HfO$_{2\pm x}$ grown by reactive molecular beam epitaxy (MBE). The oxidation conditions induce a switching between ($\bar{1}11$) and (002) texture of…

Materials Science · Physics 2015-06-12 Erwin Hildebrandt , Jose Kurian , Lambert Alff

The development of ferromagnetism in Mn-doped Bi2Te3 is characterized through measurements on a series of single crystals with different Mn content. Scanning tunneling microscopy analysis shows that the Mn substitutes on the Bi sites,…

Magnetisms in $p$-type monolayer GaX (X=S,Se) is investigated by performing density-functional calculations. Due to the large density of states near the valence band edge, these monolayer semiconductors are ferromagnetic within a small…

Mesoscale and Nanoscale Physics · Physics 2014-09-18 Sianxin Wu , Xia Dai , Hongyi Yu , Heng Fan , Jiangping Hu , Wang Yao

We study the formation energies of native point defects in GaN through density-functional theory. In our first-principles scheme, the band edges are positioned in accord with hybrid density functional calculations, thus yielding a band-gap…

Materials Science · Physics 2017-04-12 Giacomo Miceli , Alfredo Pasquarello

We have studied the evolution of the magnetic, electronic, and structural properties of annealed epilayers of Ga1-xMnxAs grown by low temperature molecular beam epitaxy. Annealing at the optimal temperature of 250 C for less than 2 hours…

Materials Science · Physics 2009-11-07 S. J. Potashnik , K. C. Ku , S. H. Chun , J. J. Berry , N. Samarth , P. Schiffer

We present an experimental investigation of the magnetic, electrical and structural properties of Ga0.94Mn0.06As1-yPy layers grown by molecular beam epitaxy on GaAs substrates for y less than or equal to 0.3. X-ray diffraction measurements…

Materials Science · Physics 2009-11-13 A W Rushforth , M Wang , N R S Farley , R C Campion , K W Edmonds , C R Staddon , C T Foxon , B L Gallagher

We present an explanation of recently observed giant magnetic moment and room-temperature ferromagnetism in the dielectric GaN doped with Gd. Our approach uses the polarization mechanism of exchange interaction, which occurs if the d-level…

Materials Science · Physics 2015-05-13 V. I. Litvinov , V. K. Dugaev

The magnetization behaviors of GdMn2Ge2 and TbMn2Ge2 in the bulk and in the fine particles obtained by high-energy ball-milling are compared. Pronounced modificayions in the spontaneous, remnent and high-field magnetization in the fine…

Strongly Correlated Electrons · Physics 2015-05-18 K. Mukherjee , Kartik K Iyer , E. V. Sampathkumaran

Results of magnetisation measurements on p-type zincblende-(Ga,Mn)N are reported. In addition to a small high temperature ferromagnetic signal, we detect ferromagnetic correlation among the remaining Mn ions, which we assign to the onset of…

Ferromagnetism is observed below 10 K in [Bi0.75Te0.125Mn0.125]Te. This material has the BiTe structure, which is made from the stacking of two Te-Bi-Te-Bi-Te blocks and one Bi-Bi block per unit cell. Crystal structure analysis shows that…

Materials Science · Physics 2009-11-11 J. W. G. Bos , M. Lee , E. Morosan , H. W. Zandbergen , W. L. Lee , N. P. Ong , R. J. Cava