Momentum-resolved electronic band structure and offsets in an epitaxial NbN/GaN superconductor/semiconductor heterojunction

Abstract The electronic structure of heterointerfaces play a pivotal role in their device functionality. Recently, highly crystalline ultrathin films of superconducting NbN have been integrated by molecular beam epitaxy with the semiconducting GaN. We use soft X-ray angle-resolved photoelectron spectroscopy to directly measure the momentum-resolved electronic band structures for both NbN and GaN constituents of this Schottky heterointerface, and determine their momentum-dependent interfacial band offset as well as the band-bending profile into GaN. We find, in particular, that the Fermi states in NbN are aligned against the band gap in GaN, which excludes any significant electronic cross-talk of the superconducting states in NbN through the interface to GaN. We support the experimental findings with first-principles calculations for bulk NbN and GaN. The Schottky barrier height obtained from photoemission is corroborated by electronic transport and optical measurements. The momentum-resolved understanding of electronic properties elucidated by the combined materials advances and experimental methods in our work opens up new possibilities in systems where interfacial states play a defining role.

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Systematic first principles calculations of the effects of stacking faults defects on the 4H-SiC band structure

MRS Proceedings ◽

10.1557/proc-1246-b03-07 ◽

2010 ◽

Vol 1246 ◽

Cited By ~ 1

Author(s):

Massimo Camarda ◽

pietro delugas ◽

Andrea Canino ◽

Andrea Severino ◽

nicolo piluso ◽

...

Keyword(s):

First Principles ◽

Density Functional ◽

Stacking Faults ◽

Perfect Crystal ◽

First Principles Calculations ◽

Electronic Band ◽

Functional Theory ◽

Experimental Findings ◽

Electronic Band Structures ◽

Formation Energies

AbstractShockley-type Stacking faults (SSF) in hexagonal Silicon Carbide polytypes have received considerable attention in recent years since it has been found that these defects are responsible for the degradation of forward I-V characteristics in p-i-n diodes. In order to extend the knowledge on these kind of defects and theoretically support experimental findings (specifically, photoluminescence spectral analysis), we have determined the Kohn-Sham electronic band structures, along the closed path Γ-M-K-Γ, using density functional theory. We have also determined the energies of the SSFs with respect to the perfect crystal finding that the (35) and (44) SSFs have unexpectedly low formation energies, for this reason we could expect these two defects to be easily generated/expanded either during the growth or post-growth process steps.

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Photoelectron spectroscopy on single crystals of organic semiconductors: experimental electronic band structure for optoelectronic properties

Journal of Materials Chemistry C ◽

10.1039/d0tc00891e ◽

2020 ◽

Vol 8 (27) ◽

pp. 9090-9132 ◽

Cited By ~ 3

Author(s):

Yasuo Nakayama ◽

Satoshi Kera ◽

Nobuo Ueno

Keyword(s):

Band Structure ◽

Single Crystals ◽

Organic Semiconductors ◽

Organic Semiconductor ◽

Photoelectron Spectroscopy ◽

Electronic Band Structure ◽

Band Structures ◽

Electronic Band ◽

Hybrid Perovskite ◽

Electronic Band Structures

Methodologies and experimental achievements for exploration into electronic band structures of organic semiconductor and hybrid perovskite single crystals are reviewed.

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Systematic First Principles Calculations of the Effects of Stacking Fault Defects on the 4H-SiC Band Structure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.645-648.283 ◽

2010 ◽

Vol 645-648 ◽

pp. 283-286 ◽

Cited By ~ 8

Author(s):

Massimo Camarda ◽

Pietro Delugas ◽

Andrea Canino ◽

Andrea Severino ◽

Nicolò Piluso ◽

...

Keyword(s):

First Principles ◽

Density Functional ◽

Stacking Faults ◽

Perfect Crystal ◽

First Principles Calculations ◽

Electronic Band ◽

Functional Theory ◽

Experimental Findings ◽

Electronic Band Structures ◽

Formation Energies

Shockley-type Stacking faults (SSF) in hexagonal Silicon Carbide polytypes have received considerable attention in recent years since it has been found that these defects are responsible for the degradation of forward I-V characteristics in p-i-n diodes. In order to extend the knowledge on these kind of defects and theoretically support experimental findings (specifically, photoluminescence spectral analysis), we have determined the Kohn-Sham electronic band structures, along the closed path Γ-M-K-Γ, using density functional theory. We have also determined the energies of the SSFs with respect to the perfect crystal finding that the (35) and (44) SSFs have unexpectedly low formation energies, for this reason we could expect these two defects to be easily generated/expanded either during the growth or post-growth process steps.

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Attosecond intra-valence band dynamics and resonant-photoemission delays in W(110)

Nature Communications ◽

10.1038/s41467-021-23650-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

S. Heinrich ◽

T. Saule ◽

M. Högner ◽

Y. Cui ◽

V. S. Yakovlev ◽

...

Keyword(s):

Valence Band ◽

Photoelectron Spectroscopy ◽

Electronic Band Structure ◽

Photoelectric Effect ◽

Final State ◽

Electronic Band ◽

Time Resolved ◽

Resonant Photoemission ◽

Pulse Trains ◽

Electron Correlation Effects

AbstractTime-resolved photoelectron spectroscopy with attosecond precision provides new insights into the photoelectric effect and gives information about the timing of photoemission from different electronic states within the electronic band structure of solids. Electron transport, scattering phenomena and electron-electron correlation effects can be observed on attosecond time scales by timing photoemission from valence band states against that from core states. However, accessing intraband effects was so far particularly challenging due to the simultaneous requirements on energy, momentum and time resolution. Here we report on an experiment utilizing intracavity generated attosecond pulse trains to meet these demands at high flux and high photon energies to measure intraband delays between sp- and d-band states in the valence band photoemission from tungsten and investigate final-state effects in resonant photoemission.

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Electronic Band Structure of Rhombohedral Arsenic Studied by Highly Angle-Resolved Ultraviolet Photoelectron Spectroscopy

Proceedings of the 17th International Conference on the Physics of Semiconductors ◽

10.1007/978-1-4615-7682-2_240 ◽

1985 ◽

pp. 1067-1070 ◽

Cited By ~ 1

Author(s):

H. Tokailin ◽

T. Takahashi ◽

T. Sagawa ◽

K. Shindo

Keyword(s):

Band Structure ◽

Photoelectron Spectroscopy ◽

Electronic Band Structure ◽

Ultraviolet Photoelectron Spectroscopy ◽

Electronic Band

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Physical Properties Investigations of Ternary-Layered Carbides M2PbC (M = Ti, Zr and Hf): First-Principles Calculations

Crystals ◽

10.3390/cryst11121445 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1445

Author(s):

Tahani A. Alrebdi ◽

Mohammed Benali Kanoun ◽

Souraya Goumri-Said

Keyword(s):

Elastic Constants ◽

First Principles ◽

Mechanical Stability ◽

Electronic Band Structure ◽

Max Phase ◽

Mechanical And Thermal Properties ◽

First Principles Calculations ◽

Electronic Band ◽

Bonding Properties ◽

Structure Density

We investigated structure optimization, mechanical stability, electronic and bonding properties of the nanolaminate compounds Ti2PbC, Zr2PbC, and Hf2PbC using the first-principles calculations. These structures display nanolaminated edifices where MC layers are interleaved with Pb. The calculation of formation energies, elastic moduli and phonons reveal that all MAX phase systems are exothermic, and are intrinsically and dynamically stable at zero and under pressure. The mechanical and thermal properties are reported with fundamental insights. Results of bulk modulus and shear modulus show that the investigated compounds display a remarkable hardness. The elastic constants C11 and C33 rise more quickly with an increase in pressure than that of other elastic constants. Electronic and bonding properties are investigated through the calculation of electronic band structure, density of states, and charge densities.

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First-Principles Calculations of Electronic Band Structures of High Pressure Phase of Solid Oxygen.

The Review of High Pressure Science and Technology ◽

10.4131/jshpreview.7.178 ◽

1998 ◽

Vol 7 ◽

pp. 178-180 ◽

Cited By ~ 11

Author(s):

M. Otani ◽

K. Yamaguchi ◽

H. Miyagi ◽

N. Suzuki

Keyword(s):

High Pressure ◽

First Principles ◽

High Pressure Phase ◽

First Principles Calculations ◽

Band Structures ◽

Electronic Band ◽

Solid Oxygen ◽

Electronic Band Structures ◽

Pressure Phase

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First-Principles Study on the Electronic Structure of Bulk and Single-Layer Boehmite

NANO ◽

10.1142/s1793292018501382 ◽

2018 ◽

Vol 13 (12) ◽

pp. 1850138

Author(s):

Seungwook Son ◽

Dongwook Kim ◽

Sutassana Na-Phattalung ◽

Jisoon Ihm

Keyword(s):

Hydrogen Bonding ◽

First Principles ◽

Single Layer ◽

Layered Materials ◽

Two Dimensional ◽

First Principles Calculations ◽

Promising Candidate ◽

Electronic Band ◽

2D Layered Materials ◽

Electronic Band Structures

Two-dimensional (2D) or layered materials have a great potential for applications in energy storage, catalysis, optoelectronics and gas separation. Fabricating novel 2D or quasi-2D layered materials composed of relatively abundant and inexpensive atomic species is an important issue for practical usage in industry. Here, we suggest the layer-structured AlOOH (Boehmite) as a promising candidate for such applications. Boehmite is a well-known layer-structured material and a single-layer can be exfoliated from the bulk boehmite by breaking the interlayer hydrogen bonding. We study atomic and electronic band structures of both bulk and single-layer boehmite, and also obtain the single-layer exfoliation energy using first-principles calculations.

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