Spiral growth and threading dislocations for molecular beam epitaxy of PbTe on BaF2 (111) studied by scanning tunneling microscopy

Springholz, G.; Ueta, A. Y.; Frank, N.; Bauer, G.

doi:10.1063/1.116855

Cited by 67 publications

(40 citation statements)

References 7 publications

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“…The FWHM varies in a range from 160 to 250 arcsec for layer thickness between 0.4 and 2.0 µm, and increases monotonically from 160 to 230 arcsec as the layer increases its thickness until 9 µm. This behavior is opposed to what is expected for this type of epitaxial layer, as in the case of PbTe on BaF 2 , in which the density of threading dislocations, and hence the FWHM, decreases as the film becomes thicker [7]. We think that Sn diffusion may be one reason to explain this unusual behavior.…”

Section: Resultscontrasting

confidence: 44%

“…3. A value of 9x10 8 cm −2 is found for the 7.09 µm thick SnTe film, which is much higher than 5x10 6 cm −2 reported for PbTe/BaF 2 film with equivalent thickness [7]. Since the lattice mismatch is smaller in the SnTe case, a smaller value for the dislocation density would be expected.…”

Section: Resultsmentioning

confidence: 74%

“…One can clearly observe the spirals with monolayer eps near the threading dislocations, similar to the PbTe BaF 2 growth. Spiral growth AFM images have been ported for PbTe grown by MBE on BaF 2 substrate [7,11]. was shown that PbTe growth is totally dominated by irals formed around threading dislocations that originate om the 4.2% lattice mismatch to the substrate.…”

Section: Discussionmentioning

confidence: 99%

“…This kind of compound finds application in the construction of thermoelectric generators and infrared detectors [4][5]. The study of structural properties of IV-VI compounds related to misfit and threading dislocations in systems like PbTe, PbSe and PbTe 1−x Se x deposited on different substrates, such as KCl, BaF 2 , Si and PbSe have been done by several groups [6][7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

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Characterization of SnTe films grown by molecular beam epitaxy

Mengui¹,

Abramof²,

Rappl³

et al. 2006

Braz. J. Phys.

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A series of SnTe layers with thicknesses varying from 0.42 to 9.1 µm were grown by molecular beam epitaxy on (111) BaF 2 substrates. The SnTe lattice parameter was found to be 6.331Å as determined from x-ray diffraction spectra measured in the triple-axis configuration. The FWHM of the (222) SnTe x-ray rocking curves indicated a good crystalline quality and an unusual dependence on layer thickness. Atomic force microscopy (AFM) of the SnTe surface revealed spirals with monolayer steps formed around threading dislocations, similar to the PbTe on BaF 2 epitaxy. The dislocation density was estimated from the AFM picture to be 9x10 8 cm −2 . Small black pits corresponding to holes that were left during growth were also observed on the AFM images. Sn diffusion can be a possible reason for these pits and the relatively high dislocation density. Electrical measurements showed that the SnTe epilayers present a typical p-type carrier concentration around 10 20 cm −3 almost temperature independent and a Hall mobility which decreases from 10 4 to 10 3 cm 2 /V.s as the temperature increases from 10 to 350K.

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Section: Resultscontrasting

confidence: 44%

Section: Resultsmentioning

confidence: 74%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Characterization of SnTe films grown by molecular beam epitaxy

Mengui¹,

Abramof²,

Rappl³

et al. 2006

Braz. J. Phys.

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“…Additionally, the system contains a significant number of threading dislocations formed during the initial growth on the BaF 2 surface as a result of 4.2% lattice mismatch. The application of a thick buffer layer reduces the dislocation density, but it remains still significant in the QW region (at least at the level of 10 7 cm −2 ) [22]. The dislocation density strongly grows when approaching the substrate, and as close as 0.5 µm from BaF 2 a thin p + interfacial layer is formed [23].…”

Section: Properties Of Initial Pbte Quantum Wellsmentioning

confidence: 99%

Ballistic Transport Phenomena in Nanostructures of Paraelectric Lead Telluride

Grabecki

2007

Acta Phys. Pol. A

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This is a review of our recent developments in the physics of lead telluride nanostructures. PbTe is a IV-VI narrow gap paraelectric semiconductor, characterized by the huge static dielectric constant ε > 1000 at helium temperatures. We nanostructurized this material by means of e-beam lithography and wet chemical etching of modulation doped PbTe/Pb 1−x Eu x Te quantum wells. Magnetoresistance measurements performed on the nanostructures revealed a number of magnetosize effects, confirming a ballistic motion of the carriers. The most important observation is that the conductance of narrow constrictions shows a precise zero-field quantization in 2e 2 /h units, despite a significant amount of charged defects in the vicinity of the conducting channel. This unusual result is a consequence of a strong suppression of the Coulomb potential fluctuations in PbTe, an effect confirmed by numerical simulations. Furthermore, the orbital degeneracy of electron waveguide modes can be controlled by the width of PbTe/Pb1−xEuxTe quantum wells, so that unusual sequences of plateau conductance can be observed. Finally, conductance measurements in a nonlinear regime allowed for an estimation of the energy spacing between the one-dimensional subbands.

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Giant Rashba Splitting in Pb_1–_xSn_xTe (111) Topological Crystalline Insulator Films Controlled by Bi Doping in the Bulk

et al. 2016

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to external perturbations. [10,15,16] Therefore, the trivial to nontrivial topological phase transition can be controlled by many different means, such as by varying temperature, [1,6] pressure, [2] hybridization in ultrathin film geometries, [17][18][19] magnetic interactions, [20] or by breaking of mirror symmetries by strain, [16,[21][22][23] electrostatic fields, [18] or ferroelectric (FE) lattice distortions. [24,25] This provides ample degrees of freedom for topology control not available in conventional Z 2 TIs. For this reason, TCIs offer an ideal template for observation of exotic phenomena such as partially flat band helical snake states and interfacial superconductivity, [16] large-Chern-number quantum anomalous Hall effect, [26] as well as for realization of novel topology-based devices such as topological photodetectors, [23] spin transistors, [18] and spin torque devices. [27] For most of such applications, thin film structures with precisely controlled composition and Fermi level are required. Up to now, most work has been performed on highly p-type bulk crystals exploiting the natural (001) cleavage plane of the IV-VI compounds, [3,4,6] whereas for other surface orientations and practical devices epitaxial TCI film structures are required. [18,[28][29][30][31][32] The (111) orientation is particularly interesting due to the polar nature of its surface [12] as well as the ease of lifting the fourfold valley degeneracy at the L-points of the Brillouin zone (BZ) [33] by opening a gap at particular Dirac points by strain [16] and quantum confinement [17][18][19] to induce a transition from a TCI to a normal Z 2 -TI material. [25]

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Spiral growth and threading dislocations for molecular beam epitaxy of PbTe on BaF2 (111) studied by scanning tunneling microscopy

Cited by 67 publications

References 7 publications

Characterization of SnTe films grown by molecular beam epitaxy

Characterization of SnTe films grown by molecular beam epitaxy

Ballistic Transport Phenomena in Nanostructures of Paraelectric Lead Telluride

Giant Rashba Splitting in Pb_1–_xSn_xTe (111) Topological Crystalline Insulator Films Controlled by Bi Doping in the Bulk

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Spiral growth and threading dislocations for molecular beam epitaxy of PbTe on BaF2 (111) studied by scanning tunneling microscopy

Cited by 67 publications

References 7 publications

Characterization of SnTe films grown by molecular beam epitaxy

Characterization of SnTe films grown by molecular beam epitaxy

Ballistic Transport Phenomena in Nanostructures of Paraelectric Lead Telluride

Giant Rashba Splitting in Pb1–xSnxTe (111) Topological Crystalline Insulator Films Controlled by Bi Doping in the Bulk

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Giant Rashba Splitting in Pb_1–_xSn_xTe (111) Topological Crystalline Insulator Films Controlled by Bi Doping in the Bulk