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Observation of zero linewidth enhancement factor at excited state band in quantum dot laser
Electronics Letters. 2015. Vol. 51. No. 21. P. 1686–1688.
The linewidth enhancement factor (LEF) of an InAs/InGaAs quantum dot Fabry-Pérot laser in a wide wavelength range from 1110 to 1300 nm, including ground state (GS) and exited state (ES) bands, is studied. LEF spectra were derived from amplified spontaneous emission spectra measured below the threshold in the pulse regime. The ES optical transition is characterised by significantly lower values of the LEF (≤0.54) as compared to the GS (≥1.21). Moreover, a zero LEF is observed within the ES spectral band. At sufficiently high currents, a near-zero LEF (|α| ≤ 0.1) is achieved in a wide spectral interval from 1146 to 1175 nm, in which the optical gain is not less than 9 cm-1.
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Nikitiuk B., Lenev D., Pisarev V. et al., Journal of Colloid and Interface Science 2026 Vol. 718 Article 140444
Hypothesis:Accurate determination of interfacial tension values is crucial for many modeling applications in the oil and gas industry. However, many of the presently used empirical and theoretical models show poor prediction accuracy and do not allow for direct consideration of the concentrations of gases and salts dissolved in the system as well as the specific ...
Added: October 28, 2026
Deshchenya V., Nikolay D. Kondratyuk, Sivakova A. et al., Chemical Engineering Sciences 2027 Vol. 337 Article 124616
Accurate prediction of complex formulation viscosity is crucial for the lubricant industry and engineering processes. However, developing generalizable models remains challenging due to the complexity of industrial mixtures and the scarcity of public experimental data, often resulting from corporate proprietary restrictions. This study presents a machine-learning workflow for viscosity estimation from a proprietary pseudonymized dataset, ...
Added: October 28, 2026
Zubov A., Zubov A., Малявко, Я. et al., Computer Physics Communications 2025 Vol. 317 Article 109860
The concept of representative volume (REV, or RVE in material sciences) is the cornerstone of continuum scale models – one needs to get the volume big enough so that it could be represented with an averaged value (scalar, vector or tensorial, etc.). While REV should be established in all larger scale simulations, this is rarely ...
Added: October 28, 2026
Budkov Y., Annals of Physics 2026 Vol. 495 No. 3 Article 170796
We study the density-matrix kinetics of a charged test particle in two types of Coulomb environment. For a prescribed Gaussian potential, averaging the random-unitary dynamics leads to a Born–Novikov memory equation; Novikov’s identity is exact, but its closure requires a second-order approximation. An equilibrium quantum bath instead yields a Born–Redfield equation with ordered correlators and ...
Added: October 26, 2026
Alexander S. Rabinowitch, International Journal of Modern Physics A 2026 Vol. 41 No. 30 Article 2650168
In this paper, we study a new class of wave solutions to the SU(2) Yang-Mills equations in the
region outside field sources. They represent a significant addition to the wave solutions obtained
in our previous publications describing non-Abelian transverse progressive waves propagating
in the direction of the Cartesian z-axis. In the new paper, wave solutions to the considered
system ...
Added: October 26, 2026
D.V. Khomitsky, Lavrukhina E. A., Krasavin D. P. et al., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 114 No. 22 Article 225414
We study coherent electric manipulation of magnetic field induced localized states at a double kink of a helical edge in a HgTe/CdHgTe quantum well. An in-plane magnetic field opens a gap in the one-dimensional (1D) edge spectrum, while changes in the edge orientation generate localized in-gap states at the kinks. We show that, for suitable ...
Added: October 23, 2026
Budkov Y., Kalikin N., Journal of Chemical Physics 2026 Vol. 165 No. 16 Article 164108
We derive the local pressure tensor generated by the original Rosenfeld fundamental measure theory (FMT) for hard-sphere fluids from an arbitrary infinitesimal deformation. The variation of a finite-distance FMT kernel is written via the line integrals of the local deformation gradient along the straight segment connecting its end points. The resulting symmetric pressure tensor consists ...
Added: October 22, 2026
Ивченко В. С., Иевлева В. А., Matienko D. et al., Журнал технической физики 2026 № 9 С. 1738–1749
Задача о возбуждении бегущих фонон-поляритонных волн на поверхности полярного кристалла падающей извне световой волной (с частотой, близкой к частоте решеточных колебаний) решена теоретически только для бесконечной открытой поверхности кристалла. В случаях, когда часть поверхности покрыта металлической маской, препятствующей проникновению возбуждающего излучения к атомам среды, и эта маска имеет произвольную форму, общепризнанного решения неоднородной задачи нет. ...
Added: October 20, 2026
Logvenkov S. A., Известия РАН. Механика жидкости и газа 2026 № 3 С. 59–75
The problem of the evolution of cell volume fraction in a spherical aggregate composed of cells,
extracellular matrix, and fluid is considered. The aggregate is surrounded by extracellular matrix. The
problem formulation employs a multiphase model of a biological continuum, previously developed by the
author, consisting of two actively interacting solid phases and a fluid. The propagation of ...
Added: October 20, 2026
Lavrukhina E. A., Krasavin D. P., Krishtopenko S. S. et al., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 114 No. 22 Article 225414
We study coherent electric manipulation of magnetic field induced localized states at a double kink of a helical edge in a HgTe/CdHgTe quantum well. An in-plane magnetic field opens a gap in the one-dimensional (1D) edge spectrum, while changes in the edge orientation generate localized in-gap states at the kinks. We show that, for suitable ...
Added: October 19, 2026
Смерчанский П. С., Koledov V. V., Kamantsev A. P. et al., Physics of Metals and Metallography 2026 Vol. 127 No. 6-7 P. 689–693
Heusler alloys of the Ni2MnX family, where X = Ga, In, Sn, …, which have been shown to exhibit
giant magnetocaloric effect (MCE) and magnetically controlled shape memory effect due to thermoelastic
magnetostructural phase transition (MSPT), continue to attract attention. However, these functional properties are fully manifested in strong magnetic fields of at least several T. Currently, ...
Added: October 19, 2026
Zaikin A., Kalenkov M. S., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 114 Article 214502
We propose a microscopic scheme that allows to describe ac Josephson effect in superconducting junctions
in terms of dissipative quantum dynamics of subgap Andreev bound states. This approach is particularly useful
for highly transparent junctions at subgap bias voltages in which case a nontrivial combination of Landau-Zener
tunneling between Andreev levels and their instability due to quasiparticle escape ...
Added: October 18, 2026
Zaikin A., Kalenkov M. S., Physical Review Letters 2026 Vol. 137 Article 076004
With the aid of a microscopic theory we derive an effective Hamiltonian that controls quantum dynamics
of Andreev states in superconducting nanojunctions out of equilibrium. Resolving the corresponding
Schrödinger-like equation we obtain the “wave functions” for Andreev levels and evaluate electric current
across the junction in the presence of an external voltage bias.We demonstrate that quantum interference of
Andreev ...
Added: October 18, 2026
Тукачев Н. В., Bataev V., Abramenkov A. et al., Computational and Theoretical Chemistry 2016 No. 1080 P. 23–32
Electronic state calculations, such as equilibrium geometry parameters, harmonic vibrational frequencies and potential barriers to conformational transitions (as well as conformer energy differences in excited states), using ab initio methods, such as MP2, CCSD(T), CASSCF, CASPT2 and MRCI, were carried out on the formamide molecule in the ground (S0) and the lowest excited singlet (S1) ...
Added: October 14, 2026
Тукачев Н. В., Bataev V. А., Godunov I. А., Journal of Quantitative Spectroscopy and Radiative Transfer 2016 Vol. 177 P. 291–300
For conformers of the N-methylformamide (HCONHCH3) molecule, calculations of equilibrium geometry parameters, harmonic vibration frequencies, energy differences and potential barriers to conformational transitions were performed in the ground (S0) and lowest excited singlet (S1) and triplet (T1) electronic states. In the S0 state, the molecule exists in trans and cis stable conformations (having Cs symmetry). ...
Added: October 14, 2026
Тукачев Н. В., Bataev V. А., Godunov I. А., Journal of Quantitative Spectroscopy and Radiative Transfer 2017 Vol. 192 P. 30–41
For acetamide molecule (CH3CONH2) in the ground (S0) and lowest excited singlet (S1) and triplet (T1) electronic states calculations of equilibrium geometry parameters, harmonic vibrational frequencies and barriers to conformational transitions (also conformer energy differences in excited states) using following ab initio methods: MP2, CCSD(T), CASSCF, CASPT2 and MRCI were performed. One-, two- and three-dimensional ...
Added: October 14, 2026
Тукачев Н. В., Bataev V. A., Godunov I. A., Computational and Theoretical Chemistry 2017 Vol. 1113 P. 82–93
Equilibrium geometry parameters, harmonic vibrational frequencies and barriers to conformational transitions and conformer energy differences for N-methylacetamide (CH3CONHCH3) molecule in S0, S1 and T1 electronic states were calculated in MP2 (S0) and CASPT2 (S1, T1) levels of theory. It is known that there are two planar (or effectively planar) conformers of N-methylacetamide in the ground ...
Added: October 14, 2026
Тукачев Н. В., Maslennikov D., Sosorev A. et al., The Journal of Physical Chemistry Letters 2019 Vol. 10 No. 12 P. 3232–3239
Conformational space of polyphenylenevinylene oligomers is systematically investigated computationally at energies relevant for room temperature dynamics in a solvent and in a solid state. Our calculations show that optimal oligomer structures are essentially planar. However, lack of a deep minimum at the planar geometry allows for large molecular deformations even at very low temperatures. At ...
Added: October 14, 2026
Timur Teregulov, Elena R. Loubenets, / Series Quantum Physics "arXiv". 2026. No. 2609.31472.
We develop a new three-party quantum secret-sharing (QSS) protocol based on a three-qubit W state. This protocol encodes the secret-sequence bits using X gates and employs randomly selected Hadamard operations and measurement bases to generate information and security-test rounds. We evaluate the efficiency of the proposed protocol and analyze its security against an internal adversary ...
Added: September 28, 2026
Shabanov N., Kuricheva O., Kurbatova J. et al., / Series Working Papers SSRN "Department of Economics Ca’ Foscari University of Venice". 2026.
The carbon balance of an ecosystem is the difference between Gross Primary Productivity (GPP) and Ecosystem Respiration (Reco) as expressed by Net Ecosystem Exchange (NEE). While remote sensing retrievals of GPP have reached maturity, Reco estimation remains underexplored and ultimately cast bias on NEE. Here we present an end-to-end multi-scale analysis of the mechanism of ...
Added: August 21, 2026
Ponomarenko A., / Series Computer Science "arxiv.org". 2025.
This paper addresses the challenge of merging hierarchical navigable small world (HNSW) graphs, a critical operation for distributed systems, incremental indexing, and database compaction. We propose three algorithms for this task: Naive Graph Merge (NGM), Intra Graph Traversal Merge (IGTM), and Cross Graph Traversal Merge (CGTM). These algorithms differ in their approach to vertex selection ...
Added: July 30, 2026
Piontkovski D., / Series arXiv "math". 2026.
A noncommutative projective variety is defined, following Artin and Zhang, by a graded coherent algebra 𝐴. The category of coherent sheaves is then the quotient qgr(𝐴) of the category of finitely presented graded modules by the subcategory of torsion modules. We consider the categorical and polynomial entropies of the Serre twist, that is, of the ...
Added: June 23, 2026
Piontkovski D., / Series arXiv "math". 2025.
If a symmetric multilinear algebra is weakly nil, then it is Engel. This result may be regarded as an infinite-dimensional analogue of the well-known Jacobian theorem, which states that if a polynomial mapping has a polynomial inverse, then its Jacobian matrix is invertible. This refines a theorem of Gerstenhaber and partially answers a question posed ...
Added: June 23, 2026
Shipilov F., Barnyakov A., Ivanov A. et al., / Series Physics "arxiv.org". 2026.
A fast simulation of the detector response is a vital task in high-energy physics (HEP). Traditional Monte-Carlo methods form the backbone of modern particle physics simulation software but are computationally expensive. We present a machine-learning-based approach to fast simulation of the Focusing Aerogel Ring Imaging Cherenkov (FARICH) detector response. Given a particle track and momentum, ...
Added: May 19, 2026