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One-dimensional structures such as nanowires (NWs) show great promise in tailoring the rates of hot carrier thermalization in semiconductors with important implications for the design of efficient hot carrier absorbers. However, fabrication of high-quality, phase-pure crystal structures and control of their intrinsic electronic properties can be challenging, raising concerns about the role of competing radiative and non-radiative recombination mechanisms that govern hot carrier effects. Here, we elucidate the impact of crystal purity and altered electronic properties on the hot carrier properties by comparing two classes of III-V semiconductor NW arrays with similar band-gap energies and geometries, yet different crystal quality: one composed of GaAsSb NWs, free of planar stacking defects, and the other InGaAs NWs with a high density of stacking defects. Photoluminescence spectroscopy demonstrates distinct hot carrier effects in both NW arrays; however, the InGaAs NWs with lower crystal quality exhibit stronger hot carrier effects, as evidenced by increased carrier temperature under identical photoabsorptivity. This difference arises from higher rates of Auger recombination in the InGaAs NWs due to their increased n-type conductivity, as confirmed by excitation power-dependent measurements. Our findings suggest that while enhancing material properties is crucial for improving the performance of hot carrier absorbers, optimizing conditions to increase the rates of Auger recombination will further boost the efficiency of these devices., Comment: 13 pages, 4 figures

We report the discovery of a bright pulse having a dispersion measure (DM) equal to 134.4 \pm 2 pc cm^{-3}, a peak flux density (S_p) equal to 20 \pm 4 Jy and a half-width (W_e) equal to 211 \pm 6 ms. The excessive DM of the pulse, after taking into account the Milky Way contribution, is 114 pc cm^{-3} that indicates its extragalactic origin. Such value of DM corresponds to the luminosity distance 713 Mpc. The above parameters make the pulse to be a reliable candidate to the fast radio burst (FRB) event, and then it is the second FRB detected at such a large \lambda \sim 2.7 m wavelength and the first one among non-repeating FRBs. The normalized luminosity L_\nu of the event, which we have designated as FRB 20190203, estimated under assumption that the whole excessive DM is determined by the intergalactic environment toward the host galaxy, is equal to \simeq 10^{34} erg s^{-1} Hz{-1}. In addition to the study of radio data we analyzed data from the quasi-simultaneous observations of the sky in the high energy (\ge 80 keV) band by the omnidirectional detector SPI/ACS aboard the INTEGRAL orbital observatory (in order to look for a possible gamma-ray counterpart of FRB 20190203). We did not detect any transient events exceeding the background at a statistically significant level. In the INTEGRAL archive, the FRB 20190203 localization region has been observed many times with a total exposure of \sim 73.2 days. We have analyzed the data but were unable to find any reliable short gamma-ray bursts from the FRB 20190203 position. Finally we note that the observed properties of FRB 20190203 can be reproduced well in the framework of a maser synchrotron model operating in the far reverse shock (at a distance of \sim 10^{15} cm) of a magnetar. However, triggering the burst requires a high conversion efficiency (at the level of 1%) of the shock wave energy into the radio emission., Comment: submitted to PASA, 11 pages, 7 figures

We study the symmetry properties of infinite spin fields in $\rm{AdS}_4$ space which are involved in the Lagrangian model proposed in arXiv:2403.14446 where the main role is played by operator constraints. It is shown that the conditions defining infinite spin states in $\rm{AdS}_4$ space are $\mathrm{SO}(2,3)$-invariant. It is found that in the model under consideration the Casimir operators are completely fixed by the constraint operators and only one of the Casimir operators is independent. It is shown that in this model, infinite spin fields in $\rm{AdS}_4$ space are described by the most degenerate representations of the $\mathrm{SO}(2,3)$ group., Comment: 1+12 pages; v2: Typos corrected, acknowledgments added

We give new formulas for reconstructions from band-limited Hankel transform of integer or half-integer order. Our formulas rely on the PSWF-Radon approach to super-resolution in multidimensional Fourier analysis. This approach consists of combining the theory of classical one-dimensional prolate spheroidal wave functions with the Radon transform theory. We also use the relation between Fourier and Hankel transforms and Cormack-type inversion of the Radon transform. Finally, we investigate numerically the capabilities of our approach to super-resolution for band-limited Hankel inversion in relation to varying levels of noise.

The logarithm of the number of Eulerian orientations, scaled by the number of vertices, is known as the residual entropy in studies of ice-type models on graphs. The spanning tree entropy depends similarly on the number of spanning trees. We demonstrate and investigate a remarkably strong, though non-deterministic, correlation between these two entropies. This leads us to propose a new heuristic estimate for the residual entropy of regular graphs that performs much better than previous heuristics. We also study the expansion properties and residual entropy of random graphs with given degrees.

We propose an enhancement to inductive types and records in a dependent type theory, namely (co)conditions. With a primitive interval type, conditions generalize the cubical syntax of higher inductive types in homotopy type theory, while coconditions generalize the cubical path type. (Co)conditions are also useful without an interval type. The duality between conditions and coconditions is presented in an interesting way: The elimination principles of inductive types with conditions can be internalized with records with coconditions and vice versa. However, we do not develop the metatheory of conditions and coconditions in this paper. Instead, we only present the type checking., Comment: 22 pages

We introduce a continuous scale of Hilbert spaces of entire functions $P_\beta (D)$ for a bounded convex domain $D$ on the complex plane. For the parameters $\beta \in (\frac 12;\frac 32)$ a complete description of the spaces of Borel transforms of functions from $P_\beta (D)$ is given., Comment: 26 pages

Understanding the origin of hot carrier relaxation in nanowires (NWs) with one-dimensional (1D) geometry is significant for designing efficient hot carrier solar cells with such nanostructures. Here, we study the influence of Auger heating and Shockley-Read-Hall recombination on hot carrier dynamics of catalyst-free InGaAs-InAlAs core-shell NWs. Using steady-state and time-resolved photoluminescence (PL) spectroscopy the dependencies of hot carrier effects on the degree of confinement of photo-generated carriers induced by the nanowire diameter are determined at different lattice temperatures. Analysis of excitation-power dependent data and temperature-dependent PL linewidth broadening reveal that at low temperatures, strong Auger recombination and phonon-bottleneck are responsible for hot carrier effects. Our analysis gives also insights into electron-phonon and ionized impurity scattering, showing opposing trends with NW diameter, and it allows to estimate the Fr\"ohlich coupling constant for the InGaAs NWs. Conversely, with increasing lattice temperature, hot carrier relaxation rates increase due to enhanced Shockley-Read Hall and surface recombination. Time-resolved spectroscopy reveals a fourfold increase in the rate of Shockley-Read-Hall recombination from 6 ns at 10 K to 1.5 ns at 150 K. The findings suggest that minimizing defect densities in the bulk and surfaces of these NWs will be key to enhance hot carrier effects towards higher temperatures., Comment: 15 pages, 5 figures

In the present paper, using the split Casimir operators we have found the decomposition of the antisymmetric part of $\mathfrak{ad}^{\otimes 5}$. This decomposition contains the representations that appeared in the decomposition of $\mathfrak{ad}^{\otimes 4}$ and only one new representation $X_5$. The dimension of this representation has been proposed in [A.J.Macfarlane, H.Pfeiffer, J.Phys.A: Math. Gen. 36 (2003) 2305]. Our decomposition is valid for all Lie algebras., Comment: 9 pages, formulas (3.7) and (3.14) corrected

We generalize the first class constraints that describe the infinite spin irreducible $4D$ Poincar\'{e} group representation in flat space to new first class constraints in $AdS_4$ space. The constraints are realized as operators acting in Fock space spanned by the creation and annihilation operators with two-component spinor indices. As a result, we obtain a new closed gauge algebra on $AdS_4$ with the known flat space limit. Using this gauge algebra, we construct the BRST charge and derive the Lagrangian and gauge transformations for free bosonic infinite spin field theory in $AdS_4$ space., Comment: 1 + 16 pages; v4: published version

We present a new particle model that generalize for constant curvature space an infinite spin particle in flat space. The model is described by commuting Weyl spinor additional coordinates. It proved that such a model is consistent only in external gravitational field corresponding to the constant curvature spaces. Full set of the first-class constraints in the de Sitter and anti-de Sitter spaces is obtained., Comment: 1 + 14 pages; v2: Minor typos corrected, added references, slightly expanded introduction, version to appear in PLB

We review the method for constructing local relativistic fields corresponding to the Bargmann-Wigner wave functions that describe the unitary irreducible representations of the $4D$ Poincar\'{e} group. The method is based on the use of the generalized Wigner operator connecting the wave functions of induced representations and local relativistic fields. Applications of this operator for constructing massive local relativistic fields as well as massless helicity local fields and massless local infinite spin fields are considered., Comment: 1+12 pages, Contribution to the Proceedings of the International Conference on Particle Physics and Cosmology (professor V.A. Rubakov memorial conference), October 02-07, 2023, Yerevan, Armenia

In this review, the seesaw mechanism for generating the mass of active light neutrinos (both Majorana and Dirac) is considered on the basis of effective field theory. In particular, we review certain models that extend the Standard Model by introducing heavy sterile neutrinos and discuss the corresponding mechanisms for generating small masses of active neutrinos. Two Appendices briefly describe the properties of Weyl, Dirac, and Majorana spinors in four dimensions and the interrelations between such spinors. The third Appendix provides a simple proof of the theorem on Takagi diagonalization of a mass matrix for Majorana fermions., Comment: 33 pages

We derive the distribution of the maximum number of common neighbours of a pair of vertices in a dense random regular graph.The proof involves two important steps. One step is to establish the extremal independence property: the asymptotic equivalence with the maximum component of a vector with independent marginal distributions. The other step is to prove that the distribution of the number of common neighbours for each pair of vertices can be approximated by the binomial distribution.

The extension of laser cooling and trapping techniques to polyatomic molecular ions would have advanced scientific applications such as search of physics outside of the Standard Model, ultracold chemistry etc. We apply the Fock space relativistic coupled cluster method to study low-lying electronic states of molecular ions with Ra--N bonds, namely RaNCH$^+$, RaNH$^+_3$ and RaNCCH$^+_3$. Prospects of laser cooling of these species are estimated, and the peculiarities of unpaired-electron distributions are analyzed from the point of view of the molecular electronic structure. RaNH$^+_3$ and RaNCCH$^+_3$ are the first symmetric top molecular ions expected to be suitable for direct laser cooling.

We obtain a uniform decomposition into Casimir eigenspaces (most of which are irreducible) of the fourth power of the adjoint representation $\mathfrak{g}^{\otimes 4}$ for all simple Lie algebras. We present universal, in Vogel's sense, formulae for the dimensions and split Casimir operator's eigenvalues of all terms in this decomposition. We assume that a similar uniform decomposition into Casimir eigenspaces with universal dimension formulae exists for an arbitrary power of the adjoint representations., Comment: 10 pages, f-la (1.6) is corrected

Rapid progress in the experimental control and interrogation of molecules, combined with developments in precise calculations of their structure, are enabling new opportunities in the investigation of nuclear and particle physics phenomena. Molecules containing heavy, octupole-deformed nuclei such as radium are of particular interest for such studies, offering an enhanced sensitivity to the properties of fundamental particles and interactions. Here, we report precision laser spectroscopy measurements and theoretical calculations of the structure of the radioactive radium monofluoride molecule, $^{225}$Ra$^{19}$F. Our results allow fine details of the short-range electron-nucleus interaction to be revealed, indicating the high sensitivity of this molecule to the distribution of magnetization, currently a poorly constrained nuclear property, within the radium nucleus. These results provide a direct and stringent test of the description of the electronic wavefunction inside the nuclear volume, highlighting the suitability of these molecules to investigate subatomic phenomena.

An Eulerian orientation is an orientation of the edges of a graph such that every vertex is balanced: its in-degree equals its out-degree. Counting Eulerian orientations corresponds to the crucial partition function in so-called "ice-type models" in statistical physics and is known to be hard for general graphs. For all graphs with good expansion properties and degrees larger than $\log^8 n$, we derive an asymptotic expansion for this count that approximates it to precision $O(n^{-c})$ for arbitrary large $c$, where $n$ is the number of vertices. The proof relies on a new tail bound for the cumulant expansion of the Laplace transform, which is of independent interest.

We conjecture that the distribution of the edge-disjoint union of two random regular graphs on the same vertex set is asymptotically equivalent to a random regular graph of the combined degree, provided it grows as the number of vertices tends to infinity. We verify this conjecture for the cases when the graphs are sufficiently dense or sparse. We also prove an asymptotic formula for the expected number of spanning regular subgraphs in a random regular graph.

We study $k$-star decompositions, that is, partitions of the edge set into disjoint stars with $k$ edges, in the uniformly random $d$-regular graph model $\mathcal{G}_{n,d}$. We prove an existence result for such decompositions for all $d,k$ such that $d/2 < k \leq d/2 + \max\{1,\frac{1}{6}\log d\}$. More generally, we give a sufficient existence condition that can be checked numerically for any given values of $d$ and $k$. Complementary negative results are obtained using the independence ratio of random regular graphs. Our results establish an existence threshold for $k$-star decompositions in $\mathcal{G}_{n,d}$ for all $d\leq 100$ and $k > d/2$, and strongly suggest the a.a.s. existence of such decompositions is equivalent to the a.a.s. existence of independent sets of size $(2k-d)n/(2k)$, subject to the necessary divisibility conditions on the number of vertices. For smaller values of $k$, the connection between $k$-star decompositions and $\beta$-orientations allows us to apply results of Thomassen (2012) and Lov\'asz, Thomassen, Wu and Zhang (2013). We prove that random $d$-regular graphs satisfy their assumptions with high probability, thus establishing a.a.s. existence of $k$-star decompositions (i) when $2k^2+k\leq d$, and (ii) when $k$ is odd and $k < d/2$., Comment: 41 pages