Article
Materials Science, Multidisciplinary
Alexander Schuckert, Annabelle Bohrdt, Eleanor Crane, Fabian Grusdt
Summary: Quantum simulation experiments are exploring inaccessible regimes, proposing to apply time-dependent photoemission spectroscopy with large magnetic field gradients to drive Bloch oscillations of spinons in cold atom quantum simulators. This can visualize states previously invisible in the equilibrium spectrum and reveal collective interactions among spinons. The simulations suggest a possible route towards solving the mystery of Fermi arcs in cuprate materials.
Article
Physics, Multidisciplinary
L. Absil, Y. Balland, F. Pereira Dos Santos
Summary: We present a method for transporting ultracold atoms over macroscopic distances and recapturing them in a vertical mixed trap. The trap consists of a vertical lattice and a transverse confinement beam. Transport is achieved using Bloch oscillations, allowing for up to 25% atom displacement.
NEW JOURNAL OF PHYSICS
(2023)
Article
Optics
Yao Zhao, Yang Chen, Zhi-Shan Hou, Bing Han, Hua Fan, Lin-Han Lin, Xi-Feng Ren, Hong-Bo Sun
Summary: This study investigates the propagation of polarization-dependent Bloch oscillations and demonstrates the polarization-dependent Bloch period using a polymer-based gradient waveguide array. The results provide a new paradigm for two-dimensional optical Bloch modes and highlight the influence of optical polarization in the same system, enabling the observation of richer physics related to Bloch oscillations.
Article
Physics, Multidisciplinary
Ze-Hong Guo, Xue-Jia Yu, Dan-Dan Liang, Guan-Qiang Li, Zhi Li
Summary: Band structure is an important tool for characterizing the physical properties of periodic systems. This study investigates the nonlinear spectrum and current density in cold atoms with interaction-dependent dispersion, revealing the destruction of dynamical stability and loss of superfluidity due to the nonlinear loop structure caused by the interaction-dependent dispersion. Furthermore, a more complex deformation of the spectrum is induced by the repulsive interaction-dependent dispersion, including the conversion between positive and negative curvature loop structures.
Article
Chemistry, Physical
Robert Salzwedel, Andreas Knorr, Dominik Hoeing, Holger Lange, Malte Selig
Summary: We present a microscopic approach to understand the beginning of radial oscillation in silver nanoparticles. Using the Heisenberg equation of motion framework, we demonstrate that the coupled dynamics of coherent electron occupation and coherent phonon amplitude induce periodic size oscillations in the nanoparticle. Our results suggest a more direct coupling mechanism between field intensity and coherent phonons, which triggers size oscillations via optically induced electron density gradient. This mechanism is more efficient than the incoherent heating process commonly discussed in literature and provides a better explanation for the early onset of oscillations observed in recent experiments.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Alexander N. Poddubny
Summary: We conducted a theoretical study on the quantum states of two repelling spinless particles in a one-dimensional tight-binding model with a simple periodic lattice and open boundary conditions. Our research revealed that the interaction between the particles can drive nontrivial correlated two-particle states, such as bound states and edge states, and induce interaction-induced flat bands. We also found that the localization of the center of mass of the two particles enforces the localization of their relative motion, leading to the formation of bound states. Furthermore, we explored the properties of the bound states using an approximate effective non-Hermitian model for the relative motion that exhibits the non-Hermitian skin effect.
Article
Physics, Multidisciplinary
Nicolo Crescini, Samuel Cailleaux, Wiebke Guichard, Cecile Naud, Olivier Buisson, Kater W. Murch, Nicolas Roch
Summary: The modern primary voltage standard is based on the a.c. Josephson effect and the ensuing Shapiro steps, where a microwave tone applied to a Josephson junction yields a constant voltage hf/2e determined by only the microwave frequency f, Planck's constant h and the electron charge e.
Article
Materials Science, Multidisciplinary
Martino Stefanini, Massimo Capone, Alessandro Silva
Summary: In this study, a model for the motion of an impurity interacting with two Tomonaga-Luttinger liquid systems is considered. A perturbative expression for the system's evolution is provided when the impurity is injected into one of the baths with a given wave packet. The dynamics of the impurity and its effect on the baths, as well as the dynamics of the bath density and momentum density, are analyzed. The correlation between the baths is also quantified, revealing a complex pattern containing information on both the impurity motion and the baths.
Article
Optics
Zhuoxiong Liu, Chengzhi Qin, Weiwei Liu, Lingzhi Zheng, Shuaifei Ren, Bing Wang, Peixiang Lu
Summary: By creating a synthetic frequency dimension with dynamic modulation in a 2D honeycomb waveguide array, Type-I and Type-II Weyl semimetals are constructed, and the frequency evolutions of topological surface states are controlled. By cascading different types of Weyl lattices, the time-reversed evolution of frequency is achieved, including frequency negative refraction, bandwidth expansion-compression, and perfect imaging.
Article
Physics, Multidisciplinary
J. Vargas, M. Nuske, R. Eichberger, C. Hippler, L. Mathey, A. Hemmerich
Summary: The study investigated the Josephson-like dynamics of a Bose-Einstein condensate of rubidium atoms in an optical square lattice and found that the oscillation frequency scales with the relative strength of collisions. Comparisons between two models demonstrated that the observed oscillatory dynamics can be explained by the ratio of the strengths of these collision processes.
PHYSICAL REVIEW LETTERS
(2021)
Article
Optics
Helene Wetter, Zlata Fedorova, Stefan Linden
Summary: Using evanescently coupled waveguides, we investigated the propagation of surface plasmon polaritons and observed plasmonic analogs of Bloch oscillations and the Wannier-Stark ladder.
Article
Optics
J. Ramya Parkavi, V. K. Chandrasekar, M. Lakshmanan
Summary: This study investigates the stable Bloch oscillations and Landau-Zener tunneling in a non-Hermitian system exposed to external fields. Complex dispersive bands were found to be isolated in both flat-band and non-flat-band cases, potentially enabling Bloch oscillations induced by a synthetic electric field and leading to amplified Bloch oscillations for controlling transport phenomena in non-Hermitian systems.
Article
Optics
Truong X. Tran, Hue M. Nguyen, Dung C. Duong
Summary: In this paper, we simulate the optical analogs of the relativistic quantum electron-positron dynamic pair production and annihilation processes in a binary waveguide array consisting of straight and curved sections. The results show excellent agreement between the discrete model based on binary waveguide arrays and the truly continuous Dirac equation in quantum field theory, in terms of the probabilities of these two processes.
Article
Astronomy & Astrophysics
B. Ekinci, Y. Pehlivan, Amol Patwardhan
Summary: This study focuses on the response of lead-based detectors to Galactic core-collapse supernovae, with particular attention to the time dependence of reaction rates. It is found that although reaction rates decrease as neutrino luminosity drops during the cooling period, the ratio of 1n to 2n event rates still changes with the evolving conditions in the supernova due to the changing character of neutrino flavor transformations, limited to a few percent.
Article
Physics, Multidisciplinary
W. Rodriguez-Cruz, J. C. Torres-Guzman, A. Diaz-de-Anda
Summary: By introducing a gradient in the length distribution of N weakly coupled beams, the elastic equivalent of the Wannier-Stark ladder is obtained in a system governed by two coupled second-degree differential equations, occurring from the third band of states onwards, unlike other classical systems.
Article
Physics, Multidisciplinary
Yuriko Baba, Francisco Dominguez-Adame, Gloria Platero, Rafael A. Molina
Summary: The study focused on the effect and control of Rashba spin-orbit coupling on the Fermi arcs of topological Dirac semimetals. Analyzing the rotation of surface state spins and the spin-dependent two-terminal conductance reveals the potential for spintronic applications in the presence of disorder.
NEW JOURNAL OF PHYSICS
(2021)
Article
Multidisciplinary Sciences
Jose Luis Hernando, Yuriko Baba, Elena Diaz, Francisco Dominguez-Adame
Summary: In this study, we investigate the impact of a random distribution of non-magnetic impurities on the electron states formed at the surface of a topological insulator. By comparing the results obtained from SCBA and CPA methods, we find that the latter provides more accurate predictions regarding the spectral properties of surface states, particularly as disorder magnitude increases.
SCIENTIFIC REPORTS
(2021)
Article
Nanoscience & Nanotechnology
Carolina Martinez-Strasser, Yuriko Baba, Alvaro Diaz-Fernandez, Francisco Dominguez-Adame
Summary: The study investigates novel spherical core-shell nanoparticles with band inversion, showing robust midgap bound states and the tunability of energy levels through shell thickness. This discovery opens up possibilities for applications in electronics and optoelectronics.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2022)
Article
Physics, Applied
M. Barroso, J. Balduque, F. Dominguez-Adame, E. Diaz
Summary: This study investigates the thermal effects on spin transport in a deformable helical molecule in the presence of chiral-induced spin-orbit coupling. The carrier-lattice interaction is taken into account using the Peyrard-Bishop-Holstein model, and temperature is introduced as a stochastic noise in the Langevin approach. The results show the existence of two distinct spin-dependent polaron transport regimes as a function of temperature.
APPLIED PHYSICS LETTERS
(2022)
Article
Optics
Hyoung-In Lee, Christopher Gaul
Summary: We investigate the surface plasmon resonance in a metal-chiral medium interface and compare it with the metal-dielectric interface. The chiral case exhibits either larger or smaller phase speeds compared to the achiral case due to energy redistribution between translation and rotation. In a loss-free system, there are crossovers among dispersion curves and spatial inversions in field profiles, which are associated with anti-symmetric spin flips with respect to medium chirality. The short-wavelength limit establishes an upper bound on medium chirality.
Article
Physics, Multidisciplinary
Dunkan Martinez, Alvaro Diaz-Fernandez, Pedro A. Orellana, Francisco Dominguez-Adame
Summary: Topological superconductors are promising candidates for the search of Majorana zero modes, which are important for quantum computation. It is necessary to study the behavior of electron states in topological superconductors in the presence of magnetic or non-magnetic impurities. The focus is on scattering resonances and spin texture to understand the spin behavior of the electrons. The results show evidence of topological robustness with scattering resonances outside the superconducting gap. Non-trivial and anisotropic spin textures related to the Dzyaloshinskii-Moriya interaction are also discovered, indicating a Ruderman-Kittel-Kasuya-Yosida interaction controlled by Friedel oscillations. These findings are valuable for further investigations on many-point-impurity scattering or impurity potentials with finite range.
ANNALEN DER PHYSIK
(2023)
Article
Physics, Condensed Matter
Christopher Gaul, Santiago Cuesta-Lopez
Summary: Organic semiconductors are ideal for affordable, scalable, and sustainable electronics, LEDs, and solar cells. A machine learning model is developed to accurately and quickly estimate the HOMO and LUMO energies of a given molecular structure, addressing a challenge in finding suitable compounds for organic photovoltaic cells.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Yuriko Baba, Mario Amado, Enrique Diez, Francisco Dominguez-Adame, Rafael A. Molina
Summary: This paper proposes a method to freely adjust the Chern number in multilayered structures by applying an external electric field along the stacking direction, overcoming the previous limitation of only being able to tune the Chern number by changing doping concentration or magnetic layer width. By generating new inverted bands and collapsing the previously inverted ones through the presence of an electric field in the stacking direction, the number of Chern states can be externally tuned in the sample without modifying the layers or doping level.
Article
Physics, Fluids & Plasmas
R. P. A. Lima, A. Malyshev
Summary: This study investigates various regimes of charge transfer in DNA using the Peyrard-Bishop-Holstein model. It finds that the polaronic contribution to charge transport is irrelevant due to the instability of the polaron. An alternative fluctuation-governed charge transfer mechanism is proposed, which explains the different charge transfer regimes at different temperatures. Dynamic fluctuations in the vibrational subsystem play a key role in this mechanism.
Article
Materials Science, Multidisciplinary
Irian Sanchez-Ramirez, Yuriko Baba, Leonor Chico, Francisco Dominguez-Adame
Summary: This study investigates the impact of many-body effects on the thermoelectric efficiency of graphene nanoribbons and finds that electron-electron interactions are crucial for enhancing the thermoelectric efficiency. An experimental setup is also proposed to test the validity of the conclusions.
Article
Chemistry, Multidisciplinary
Olga Arroyo-Gascon, Yuriko Baba, Jorge Cerda, Oscar de Abril, Ruth Martinez, Francisco Dominguez-Adame, Leonor Chico
Summary: In this study, we investigate the effects of a non-magnetic impurity located at the surface of the SnTe topological crystalline insulator. We find that doping leads to a shift of the Dirac cones in energy, which strongly depends on the impurity position with respect to the surface. By comparing different geometries, we demonstrate that the surface states remain gapless in the doped semi-infinite system, while a gap opens in the slab geometry.
Proceedings Paper
Education & Educational Research
Yuriko Baba, Elena Diaz, Francisco Dominguez-Adame, Alvaro Diaz-Fernandez
Summary: In an attempt to communicate scientific breakthroughs to a wide audience, media often provide brief summaries of findings, which may not be sufficient for undergraduate students in scientific disciplines. Introducing recent research discoveries in the curriculum can be a complex but beneficial strategy, as students could be influenced by media bias and may benefit from exposure to cutting-edge research in their courses.
7TH INTERNATIONAL CONFERENCE ON HIGHER EDUCATION ADVANCES (HEAD'21)
(2021)
Article
Materials Science, Multidisciplinary
Vivian Torres Vera, Diego Mendez-Gonzalez, Diego J. Ramos-Ramos, Asmae Igalla, Marco Laurenti, Rafael Contreras-Caceres, Enrique Lopez-Cabarcos, Elena Diaz, Jorge Rubio-Retama, Sonia Melle, Oscar G. Calderon
Summary: The study analyzed the effect of Er3+ and Yb3+ dopant concentrations on the luminescence properties of nanoparticles and found that there is a significant increase in luminescence intensity as the Yb/Er ratio increases following a power-law behavior, with greater enhancement at low excitation intensities. Saturation occurs at a Yb/Er ratio of around two, with a slight peak when this ratio is around four.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
