Weak superconductivity in the surface layer of a bulk single-crystal boron-doped diamond

Бланк, В. Д.; Буга, С. Г.; Бормашов, В. С.; Денисов, В. Н.; Кириченко, А. Н.; Kulbachinskii, V. A.; Кузнецов, М. С.; Кытин, В. Г.; Kytin, G. A.; Тарелкин, С. А.; Terentiev, Sergey A.

doi:10.1209/0295-5075/108/67014

Cited by 11 publications

(11 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The fact that even low doped diamond sample has metallic heat capacity behaviour at low temperature indicates that the reason for such a behaviour is not boron doping, but most likely takes place due to metallic inclusions. An absence of a characteristic superconductivity transition peak in heat capacity which was observed on polycrystalline superconducting diamonds [4] agrees with the conclusion about surface superconductivity in single crystals evaluated on the basis of studies of structure of the samples, electrical and magnetic measurements [5].…”

Section: Resultssupporting

confidence: 85%

“…Each sample has its own α. One might connect this feature with the metallic-like behaviour of a phase which was found on the surface of the heavily boron-doped diamonds [5,10]. However in that case the metallic-like heat capacity behaviour should be closely related to boron content.…”

Section: Resultsmentioning

confidence: 88%

“…It is known that heavily boron-doped polycrystalline diamonds grown by HPHT method possess heat capacity anomaly at transition to superconducting state [3,4]. Recently we reported the superconducting transition on the as grown surface of our bulk heavily boron-doped single crystal diamonds grown by HPHT [5]. The heat capacity data at low temperatures for these diamonds could also possibly clarify the origin of superconductivity.…”

Section: Introductionmentioning

confidence: 69%

See 2 more Smart Citations

Heat capacity of bulk boron-doped single-crystal HPHT diamonds in the temperature range from 2 to 400 K

Тарелкин

Бормашов

Кузнецов

et al. 2016

J. Superhard Mater.

View full text Add to dashboard Cite

Heat capacity of bulk boron doped single crystal HPHT diamonds in the temperature range from 2 to 400 K Heat capacity С р of boron-doped single crystal diamonds grown by the temperature gradient method was studied. Boron content was about < 10 16 , ∼ 10 18 and ∼ 10 20 cm-3. Heat capacity data for all tested crystals match well within the measurement accuracy (1 %) in the temperature range of 150-400 K and obey the Debye law. At low temperatures heat capacity follows linear law possibly due to metallic inclusions in diamond bulk. Using this data the amount of metal can be calculated for each sample.

show abstract

Section: Resultssupporting

confidence: 85%

Section: Resultsmentioning

confidence: 88%

Section: Introductionmentioning

confidence: 69%

See 1 more Smart Citation

Heat capacity of bulk boron-doped single-crystal HPHT diamonds in the temperature range from 2 to 400 K

Тарелкин

Бормашов

Кузнецов

et al. 2016

J. Superhard Mater.

View full text Add to dashboard Cite

show abstract

“…We identified that the transitions to the superconducting state occur in the (111) surfaces of the as-grown BDD crystal only [ 29 ]. We found that the shift of the diamond peak correlates with a temperature of superconducting transition T c .…”

Section: Resultsmentioning

confidence: 99%

Formation of Boron-Carbon Nanosheets and Bilayers in Boron-Doped Diamond: Origin of Metallicity and Superconductivity

et al. 2016

View full text Add to dashboard Cite

The insufficient data on a structure of the boron-doped diamond (BDD) has frustrated efforts to fully understand the fascinating electronic properties of this material and how they evolve with doping. We have employed X-ray diffraction and Raman scattering for detailed study of the large-sized BDD single crystals. We demonstrate a formation of boron-carbon (B-C) nanosheets and bilayers in BDD with increasing boron concentration. An incorporation of two boron atoms in the diamond unit cell plays a key role for the B-C nanosheets and bilayer formation. Evidence for these B-C bilayers which are parallel to {111} planes is provided by the observation of high-order, super-lattice reflections in X-ray diffraction and Laue patterns. B-C nanosheets and bilayers minimize the strain energy and affect the electronic structure of BDD. A new shallow acceptor level associated with B-C nanosheets at ~37 meV and the spin-orbit splitting of the valence band of ~6 meV are observed in electronic Raman scattering. We identified that the superconducting transitions occur in the (111) BDD surfaces only. We believe that the origin of Mott and superconducting transitions is associated with the two-dimensional (2D) misfit layer structure of BDD. A model for the BDD crystal structure, based on X-ray and Raman data, is proposed and confirmed by density functional theoretical calculation.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-015-1215-6) contains supplementary material, which is available to authorized users.

show abstract

“…The B atoms are mainly incorporated into nanosheets and bilayers, enhancing the boron solubility in the diamond lattice. Since superconductivity was observed only on the BDD surface [ 12 ], there is a need for a more detailed study of the 2D layered structure on the as-grown surface. Superconductivity in the bulk of the BDD single crystal was not observed because the boron concentration was low (~ 0.13 at.%).…”

Section: Introductionmentioning

confidence: 99%

Structure Investigations of Islands with Atomic-Scale Boron–Carbon Bilayers in Heavily Boron-Doped Diamond Single Crystal: Origin of Stepwise Tensile Stress

Polyakov

Денисов

et al. 2021

Nanoscale Res Lett

View full text Add to dashboard Cite

The detailed studies of the surface structure of synthetic boron-doped diamond single crystals using both conventional X-ray and synchrotron nano- and microbeam diffraction, as well as atomic force microscopy and micro-Raman spectroscopy, were carried out to clarify the recently discovered features in them. The arbitrary shaped islands towering above the (111) diamond surface are formed at the final stage of the crystal growth. Their lateral dimensions are from several to tens of microns and their height is from 0.5 to 3 μm. The highly nonequilibrium conditions of crystal growth enhance the boron solubility and, therefore, lead to an increase of the boron concentrations in the islands on the surface up to 1022 cm−3, eventually generating significant stresses in them. The stress in the islands is found to be the volumetric tensile stress. This conclusion is based on the stepwise shift of the diamond Raman peak toward lower frequencies from 1328 to 1300 cm−1 in various islands and on the observation of the shift of three low-intensity reflections at 2-theta Bragg angles of 41.468°, 41.940° and 42.413° in the X-ray diffractogram to the left relative to the (111) diamond reflection at 2theta = 43.93°. We believe that the origin of the stepwise tensile stress is a discrete change in the distances between boron–carbon layers with the step of 6.18 Å. This supposition explains also the stepwise (step of 5 cm−1) behavior of the diamond Raman peak shift. Two approaches based on the combined application of Raman scattering and X-ray diffraction data allowed determination of the values of stresses both in lateral and normal directions. The maximum tensile stress in the direction normal to the surface reaches 63.6 GPa, close to the fracture limit of diamond, equal to 90 GPa along the [111] crystallographic direction. The presented experimental results unambiguously confirm our previously proposed structural model of the boron-doped diamond containing two-dimensional boron–carbon nanosheets and bilayers.

show abstract

Weak superconductivity in the surface layer of a bulk single-crystal boron-doped diamond

Cited by 11 publications

References 24 publications

Heat capacity of bulk boron-doped single-crystal HPHT diamonds in the temperature range from 2 to 400 K

Heat capacity of bulk boron-doped single-crystal HPHT diamonds in the temperature range from 2 to 400 K

Formation of Boron-Carbon Nanosheets and Bilayers in Boron-Doped Diamond: Origin of Metallicity and Superconductivity

Structure Investigations of Islands with Atomic-Scale Boron–Carbon Bilayers in Heavily Boron-Doped Diamond Single Crystal: Origin of Stepwise Tensile Stress

Contact Info

Product

Resources

About