arXiv subjects

Daniel Chemisana

Publications and source records attributed to Daniel Chemisana.

5 recordsLinked to original sources

arXiv2026

Coherent states in minimal-length Quantum Mechanics: inequivalent characterizations and emergent squeezing

Several approaches to quantum gravity suggest the emergence of a fundamental minimal length at the Planck scale. In quantum mechanics, this feature is naturally encoded through deformations of the Heisenberg algebra, leading to the Generalized Uncertainty Principle (GUP). While the phenomenological implications of GUP have been extensively explored, a consistent characterization of coherent states in minimal-length quantum mechanics remains elusive. In this work, we present a systematic analysis of coherent states for the one-dimensional harmonic oscillator. We show that the canonical equivalence among their standard characterizations - as eigenstates of the annihilation operator, displaced vacuum states and minimum-uncertainty wave packets - is generically lost in the presence of a minimal length. We then investigate the dynamical and semiclassical consequences of this inequivalence by comparing the evolution of generalized coherent states with that of states saturating the GUP. In particular, we demonstrate that minimal-length effects induce nontrivial deformations of phase-space trajectories and give rise to an intrinsic squeezing mechanism with no counterpart in ordinary quantum mechanics. These results establish a unified framework for coherence in GUP-based quantum theories and identify distinctive semiclassical signatures of minimal-length physics, opening a new avenue for probing quantum-gravitational effects.

quant-ph↗

arXiv2026

$κ$-entropic statistical paradigm for relativistic corrections to the Heisenberg principle

The Heisenberg position-momentum uncertainty relation is a cornerstone of quantum mechanics. However, its standard formulation is not fully consistent with special relativity. While partial understanding has been achieved in the ultra-relativistic regime, a comprehensive description is still lacking, particularly in the intermediate velocity domain, where particle speeds remain well below the speed of light yet relativistic corrections are expected to become appreciable. This regime constitutes the most promising arena for experimentally probing relativistic modifications of quantum uncertainty. By adopting a variational approach, in this work we derive a relativistic extension of the Heisenberg algebra within the framework of $κ$-deformed Kaniadakis statistics. The latter emerges from the application of the Maximum Entropy Principle to Kaniadakis entropy, a one-parameter generalization of the Boltzmann-Gibbs-Shannon entropy naturally induced by Lorentz transformations. We investigate the physical implications of the resulting uncertainty relation, deriving constraints on the Kaniadakis parameter from precision measurements of the fine-structure constant and confronting our construction with other extensions discussed in the recent literature.

quant-ph↗

arXiv2023

On mixed radial Moore graphs of diameter 3

Radial Moore graphs and digraphs are extremal graphs related to the Moore ones where the distance-preserving spanning tree is preserved for some vertices. This leads to classify them according to their proximity to being a Moore graph or digraph. In this paper we deal with mixed radial Moore graphs, where the mixed setting allows edges and arcs as different elements. An exhaustive computer search shows the top ranked graphs for an specific set of parameters. Moreover, we study the problem of their existence by providing two infinite families for different values of the degrees and diameter $3$. One of these families turns out to be optimal.

math.CO↗

arXiv2021

Spectral nature of soiling and its impact on multi-junction based concentrator systems

Soiling, which consists of dust, dirt and particles accumulated on the surface of conventional or concentrator photovoltaic modules, absorbs, scatters, and reflects part of the incoming sunlight. Therefore, it reduces the amount of energy converted by the semiconductor solar cells. This work focuses on the effect of soiling on the spectral performance of multi-junction (MJ) cells, widely used in concentrator photovoltaic (CPV) applications. Novel indexes, useful to quantify the spectral impact of soiling are introduced, and their meanings are discussed. The results of a one-year experimental investigation conducted in Spain are presented and are used to discuss how soiling impacts each of the subcells of a MJ cell, as well as the cell current-matching. Results show that soiling affects the current balance among the junctions, i.e. the transmittance losses have found to be around 4% higher in the top than in the middle subcell. The spectral nature of soiling has demonstrated to increase the annual spectral losses of around 2%. Ideal conditions for the mitigation of soiling are also discussed and found to be in blue-rich environments, where the higher light intensity at the shorter wavelengths can limit the impact of soiling on the overall production of the CPV system.

eess.SY↗

arXiv2020

Impact of spectral effects on photovoltaic energy production: A case study in the United States

The time averaged efficiency of photovoltaic modules in the field is generally lower than the efficiency measured in the laboratory under standard testing conditions due to the combined effects of temperature and spectral variability, affecting the bankability of power plant projects. We report correction factors to account for spectral effects ranging from -2% to 1.3% of the produced energy for silicon modules depending on location and collector geometry. In high irradiance locations, the energy yield advantage of trackers is underestimated by 0.4% if spectral sensitivity effects are neglected. We find a correlation between the locations most favourable for tracking, and those most favourable for multijunctions. As the photovoltaic market grows to a multi-terawatt size, these seemingly small effects are expected to have an economic impact equivalent to tens of billions of dollars in the next few decades, far out-weighting the cost of the required research effort.

physics.app-ph↗