Cavity quantum electrodynamics studies the strong interaction between matter and the electromagnetic field of an optical cavity: the enhanced interaction is useful both for reading the properties of the atoms with a fast, sensitive and weakly destructive measurement and for quantum simulation where atoms interact by exchanging photons with each other at a distance. One of the drawbacks of...
The act of a quantum measurement seems to evade the accessibility of the Schrödinger equation and its unitary time evolution [1]. In this work, we explore whether a quantum measurement on a subsystem by an apparatus can be simulated within an experimentally realizable quantum mechanical many-body system by the unitary time evolution of the many-body Schrödinger equation.
For the numerical...
An absolute atomic gravimeter and gradiometer based on atom interferometry have emerged as powerful tools for measuring the mass distribution beneath the Earth's surface. The spatial and temporal variations in gravity can be measured precisely with quantum gravimeters and gradiometers. These precise gravity measurements provide valuable information for geosciences, including geophysics,...
CMOS sensors, typically used in smartphone cameras and other commercial applications, have gained recent attention for their potential use in astronomical [1] and biological [2,3] x-ray imaging due to their improved readout speed and resolution, and lower power consumption, noise, and cost compared to their CCD counterparts. This work explores the conversion of two commercial off the shelf...
It is now well established that the ITER Tokamak divertor will be made of tungsten (Z=74). During nuclear fusion operations, the divertor will endure some of the harshest conditions in the reactor. Thus, under neutron bombardment, tungsten will undergo nuclear transmutation, forming other elements, including osmium (Z=76). On the one hand, these impurities will contribute to the radiation...
A systematic study of bosons in a one-dimensional quasiperiodic optical lattice is performed using the Quantum Monte Carlo time-dependent Variational Monte Carlo (tVMC) method [1], following the procedures established by some of the authors in an earlier study [2]. In quasiperiodic lattices, formed by the superposition of two optical lattices with incommensurate wave numbers, even a weak...
Enantiomer-selective methods - the separation of non-superimposable mirror-image chiral molecules - is critical for many industries relying on chiral purity. Traditional methods like circular dichroism exploit the spin angular momentum of light but their sensitivity is limited by the inherent molecular properties. Orbital angular momentum (OAM) in structured light offers a promising...
Building useful quantum computers means making them better as well as bigger. At Oxford Ionics we do this by combining the precision of trapped-ion qubits with the scalability of microelectronics. We replace the lasers conventionally used to manipulate ion qubits with electronics integrated directly into trap chips, which allows us to reach world-leading gate fidelities in a highly scalable...
Recently there has been growing interest in TPPS4 for applications in photodynamic therapy as photosensibilizator [1]. The monomers of this porphyrin efficiently self-associate into H- and J-aggregates in aqueous media. It is not fully understood what kind of TPPS4 configurations are building blocks of molecular aggregates. For these reasons, the aim of this study is to determine tetramers and...
The increasing interest in photoactive organic molecules for solar energy conversion systems, photocatalysis, and photodynamic therapy, requests a deep understanding of their photophysical and photochemical properties and how the microenvironment affects them. Metal phthalocyanines (MPcs), a class of highly conjugated macrocyclic compounds, are particularly promising due to their strong light...
Ultracold gases of divalent atoms excited to high Rydberg states are an exciting tool to explore subjects from fundamental Rydberg physics to quantum simulation [1]. While calcium has received little attention compared to other heavier divalent species (Sr, Yb), its unique features, including low autoionization rates or the smallest electronic affinity of all atomic species, are expected to...
Atomic magnetometers with magneto-optical signals based on Zeeman effect can achieve high sensitivity and accuracy in low magnetic fields, where the Zeeman effect is linear. In magnetic fields that exceed the Earth’s magnetic field (~0.5 G), the nonlinear Zeeman (NLZ) effect introduces errors in magnetic field measurements. The NLZ effect does not affect $^{87}$Rb ground-state sublevels with...
Due to the complexity of their internal energy level structure, controlling molecules' internal states presents a significant challenge. Most molecular ions lack closed optical cycling transitions, which prevents standard state preparation and detection techniques routinely exploited in the atomic community, as well as direct laser cooling techniques. These challenges were recently tackled for...
Over the past 15 years, the development of hybrid trapping experiments for cold atoms and ions has enabled a variety of new research directions and applications in the realm of atomic, molecular and chemical physics [1]. We introduce here an extension of this approach to the molecular domain by combining an ion trap and a molecular trap as a new way to explore low-temperature ion-molecule...
Cold atoms prepared in the volume of a high-finesse optical resonator [1] form a hybrid quantum system that can serve as an interface between photonic and atomic qubits. Bistability in the hyperfine ground state of atoms [2] is useful for quantum sensing applications, while hybridized states of light and matter will be exploited in future quantum technology applications.
We experimentally...
We present the evidence of surface magnetism detection using highly charged ions as a probe, and without any external magnetic field application [1]. Based on x-ray spectroscopy, our investigation puts an end to a longstanding controversy from contradictory studies on ion–magnetic surface interaction based on Auger spectroscopy [2,3]. We measured the $n=2 \to 1$ transition of excited argon...
Optomechanical platforms with high-quality mechanical and optical resonators have a wide application potential ranging from quantum limited sensing to long-lived storage of quantum information. Whilst exceptionally high-quality factors have been realized with structures in thin layers of dielectric or semiconducting materials, their geometries are limited by the capacity of lithographic...
Synopsis: We show how to imprint the handedness of locally chiral light into achiral matter, and how to monitor such achiral-to-chiral phase transitions in an all-optical setup. Our proof-of-principle simulations reveal that the hydrogen atom undergoes ultrafast and highly nonlinear chiral electron dynamics when exposed to an intense, ultrashort, locally chiral laser pulse, giving rise to...
We present a program speeding up the brute force calculation of the $L_d$ norms of an n×m matrix M. The $L_1$ norm stands for the local bound of the Bell expression [1], meanwhile, $L_d$ norms where $d \ge 2$ are the classical $d$-dimensional bounds of the prepare-and-measure (PM) witness [2]. In both cases, we assume binary outputs. These norms are of interest in the field of communication...
Nature relies on biological light-harvesting (LH) complexes to capture and transfer solar energy to the reaction center with supreme efficiency. These LH complexes can be modeled theoretically as subwavelength rings of optical dipoles [1-4] which partially explains their outstanding collective optical properties. Taking inspiration from the oligomeric geometry of biological LH2 complexes [5,...
Abstract
Precise manipulation of ultracold atoms is one of powerful methods for investigation of complicated fields as a quantum senser. We have investigated interactions between a dielectric surface and atoms [1, 2], and manipulation of cold atoms by optical dipole and radiative forces [3].
In this study, we have experimentally observed the loading behaviors of ultracold rubidium atoms...
We present a summary of cross sections for electron scattering on H$_2$ for fusion and astrophysical plasma-modelling applications, calculated using the molecular convergent close-coupling (MCCC) method. Accurate collisional-radiative modelling requires the input of cross sections for numerous processes, including elastic scattering, ionisation, and excitation, considering a large number of...
Electron impact recombination, (ro-)vibrational-, electronic- and dissociative excitation
of molecular cations: $AB^++e^− \rightarrow AB^*, AB^{**} \rightarrow A + B$ (DR) or ${AB^+}^* + e^−$ (RV(d)E) or $A + B^+ + e^−$ (DE) are in the heart of the molecular reactivity in all cold ionized media [1], being major charged particles destruction reactions and producing often atomic species in...
The electron-induced fluorescence of carbon monoxide (CO) was studied in a crossed electron and molecule beam experiment using optical emission spectroscopy. CO is one of the dominant carbon bearing molecules in the Universe, especially on extra-terrestrial bodies such as comets or centaurs. Many of the previous publications are focused solely on the Comet Tail system of CO$^+$ [1], because of...
Lanthanides have nowadays become of vital importance in advanced materials and technology. Applications in laser science, solar cells, fluorescent lamps and a new organic light-emitting di-odes components, as well as luminescent probes are strongly related with their optical and/or elec-tronic properties.
Samarium and its compounds are among the most frequently used lanthanides in the...
Precise spectroscopic measurements in small molecular systems such as He$_2$ and He$_2^+$ are of interest as benchmark for high-accuracy ab-initio quantum-chemical calculations in few-electron molecules [1-3].
In the case of He$_2^+$, only the lowest ($v^+=0-2$) [4-5] and highest ($v^+=22-23$) [6] vibrational levels of the X$^+$ $^2\Sigma_u^+$ electronic ground state have been...
Alkali dimers, Ak$_2$, residing on the surface of helium nanodroplets, are set into rotation and vibration, through the dynamic Stark effect, by a moderately intense 50-fs pump pulse. Coulomb explosion of dimers in the singlet X $^1\Sigma_g^+$ and triplet a $^3\Sigma_u^+$ state [1, 2], induced by an intense, delayed femtosecond probe pulse, is used to record the time-dependent nuclear...
High harmonic generation (HHG) occurs when an intense infrared laser interacts with matter, producing radiation at integer multiples of the laser's fundamental frequency [1]. It was first studied in atomic and molecular gases [1] and later extended to solids [2], enabling compact ultrafast light sources. Recent interest in the quantum properties of the driving pulse [3,4], together with...
Four-wave mixing (FWM) is a nonlinear optical process in which two (or three) interacting optical fields generate two (or one) new fields via the medium’s nonlinearity of third order $\chi^{(3)}$. Alkali vapors, especially those of Rb and Cs, exhibit exceptionally high nonlinear optical responses. Under near-resonant conditions, the third-order nonlinear susceptibility of these atomic vapors...
Organic dye molecules doped in organic host crystal provide an exquisite platform for quantum optics because they can reach Fourier-limited spectra at low temperatures. This is in large part due to the highly ordered and stable crystal structures, which provide a low-noise environment, thus minimizing spectral diffusion and dephasing. Many important fundamental studies and technological...
Detailed insight into the dynamics of elementary reactions in the gas phase can be obtained from crossed-beam reactive scattering experiments. Angle and energy differential cross-section can be obtained by combining the velocity map imaging (VMI) with crossed-beam scattering[1][2]. In this contribution, we present the differential cross-section measurement of an ion-molecule charge transfer...
Highly oriented pyrolytic graphite (HOPG) structural changes caused by gallium (Ga) im-plantation at room temperature were investigated. To monitor structural changes in the sam-ples after implantation, Raman spectroscopy was used. SRIM (Stopping and Range of Ions in Matter 2013) software was applied to determine the depth profiles of Ga implanted at dif-ferent energies and the degree of...
Molecular spectroscopy studies have been carried out on various diatomic molecular ions co-trapped with atomic ions in ion traps, including CaH$^+$, MgH$^+$, CaO$^+$, HD$^+$, N$_2^+$ and H$_2^+$, contributing to fundamental physics research and quantum information processing applications [1-6]. On a similar platform consisting of a single molecular ion co-trapped with one Ca$^+$ qubit ion, we...
Rydberg atoms exhibit strong electric dipole transitions over a large range of the electromagnetic spectrum, making them ideal candidates for hybrid quantum systems that connect the optical and microwave domains.
In this project, we plan to investigate the coupling between optically controlled Rydberg atoms and a high overtone bulk acoustic wave resonator (HBAR). Our goal is to explore the...
In recent years, my group explores intramolecular and intermolecular charge-transfer mechanisms in various ionization and neutralization processes.[1,2] Here, I will present ultrafast EUV pump – EUV probe studies of the $(CO_2)_2^+$ dynamics that we initiated by photoionization of neutral carbon dioxide dimers and probed by Coulomb explosion imaging as a function of the pump-probe time...
Josephson Oscillations (JO) have been studied in cold
atom experiments with Bose-Einstein condensates and strongly
interacting Fermi gases, where they typically occur across a thin tunneling barrier. In this work, we present measurements of JO occurring between two reservoirs containing unitary Fermi gases. The reservoirs are connected by a long, mesoscopic transport channel projected by a...
In quantum mechanics, the energy spectrum of two-dimensional electrons pierced by a uniform magnetic field are quantized into discrete, equally spaced levels, known as Landau levels (LLs). When such a system is placed inside a high-Q optical cavity and coupled strongly to a quantized cavity mode, Landau levels are then dressed by photons and form hybrid light-matter states, which I coin the...
The helium dimer in its metastable triplet state is a promising candidate to become the first homonuclear molecule ever laser-cooled. Nearly diagonal Franck-Condon factors are obtained, because the electron employed for optical cycling occupies a Rydberg orbital that doesn’t take part in the chemical bond. In addition, the general Pauli principle facilitates the closing of the cooling cycle...
Doubly charged molecular ions are elusive species that, despite their role in plasmas [1], have rarely been spectroscopically characterized. We report the first study by laser spectroscopy of the X($^3\Pi_\Omega$)-A($^3\Sigma^+$) transition of the CO⁺⁺ ion. Experimentally, a fast beam of CO⁺⁺ ions was produced from a plasma ion source. In the ground electronic state, all vibrational levels...
We have studied the loss mechanisms in a sample of trapped ultracold bosonic Feshbach molecules formed from the fermionic isotopes $^{161}$Dy and $^{40}$K. Created by sweeping a magnetic field across a low-field Feshbach resonance at 7.29 G [1], the sample consists of approximately 7000 molecules at a typical temperature of 70 nK. The molecules are spatially separated from the remaining atomic...
Liquid-Jet Photoelectron Spectroscopy (LJ-PES) [1] enables the direct study of the electronic structure of both solute and solvent, and has advanced the chemical analysis in aqueous solutions. The LJ facilitates in-vacuo continuous liquid replacement, and detection of photoelectrons with minimal collisions with evaporating water molecules.
Velocity Map Imaging (VMI) [2] provides optimal...
A Multi-Reflectron Time-of-Flight (MR-ToF) device, originally developed through a collaboration between the TU Darmstadt and the University of Greifswald [1], has been adapted to trap multiply charged helium nanodroplets (HNDs) using purely electrostatic fields. The system enables confinement of the droplets for a mean lifetime of about 14 seconds, with individual droplets surviving for over a...
We present the magnetic system constructed for the state-of-the-art $5\times 10^{-18}$ fractional frequency uncertainty Sr transportable clock developed within the “Advanced Quantum Clock For Real-World Applications” project. The system includes a compact permanent-magnets Zeeman slower, a pair of Helmholtz coils for atom trapping, and a compact set of compensation coils used to cancel out...
The study of the interactions between ion beams and biomolecules such as nucleobases, nucleosides, amino acids or peptides is a relevant topic for hadrontherapy applications. After interaction with the energetic ions, the biomolecular target could be ionized and excited. Molecular fragmentation is one of the relaxation process for such ionized/excited states. To better quantify the...
An array of closely spaced, dipole coupled quantum emitters exhibits collective energy shifts as well as super- and sub-radiance with characteristic tailorable spatial radiation patterns. As a striking example we identify a sub-wavelength sized ring of exactly 9 identical dipoles with an extra identical emitter with a extra loss channel at the center as the most efficient configuration to...
Using the photon-ion merged-beams technique at a synchrotron light source, we have measured relative cross sections for double and up to tenfold photoionization of La$^+$ ions in the energy range 820–1400 eV where resonances and thresholds occur that are associated with the excitation or ionization
of one M-shell electron. The normalization of the sum of the measured partial cross sections to...
The formation and breakage of molecular bonds is at the core of understanding and controlling chemical reactions that determine our life, quality of terrestrial environment as well as evolution of the universe. Depending on the nature of the colliding species different chemical reactions can occur.
In particular, when two molecular ions interact, this can lead to the charge transfer from an...
The DESIREE double cryogenic storage ring at Stockholm University uniquely combines the ability to store and manipulate ions for extended periods of time with the merged-beams configuration allowing studies of sub-eV collisions between ions of opposite charges. By storage alone, molecules are allowed to relax vibrationally and rotationally towards their thermal equilibrium with the cryogenic...
The last ten years or so have witnessed a tremendous growth on the detection and observation of charged molecular species in the interstellar medium (ISM), especially within the special environments provided by interstellar and circumstellar clouds. Further observations within the atmospheres of the exoplanets have confirmed the marked ubiquity of these most diverse chemical species in the...
This work explores the application of the Quantum Phase Estimation (QPE) algorithm for the non-destructive measurement of the average photon number $\langle n \rangle$ in a free field, using qubits to capture the decay dynamics of the quantum field. The protocol is implemented with 5 qubits, achieving high precision in estimating the phase associated with $\langle n \rangle$, with...
Study of information scrambling in a quantum many-body system is key to understanding the dynamics of thermalization and the evolution towards equilibrium. This work reports our experimental investigation into this topical subject by directly observing the out-of-time-order correlation (OTOC) function in a Rydberg atom array.
A key challenge in measuring the OTOC in an analog-digital...
Chaos and thermalization are interconnected phenomena that happen everywhere in life and play a crucial role in a wide range of scientific fields. A paradigmatic system that exhibits chaotic dynamics is a rotating pendulum that is periodically kicked, the so-called kicked rotor. Surprisingly, for its quantum variant, known as the quantum kicked rotor (QKR), quantum coherence prevents energy...
We report on progress towards implementing Rydberg-based spin squeezing protocols [1] using small (N < 10) ensembles of Sr atoms in magic-wavelength optical tweezers. Highly-excited Rydberg states provide new ways to engineer entanglement in optical frequency standards such as Sr and Yb atomic clocks, with the first results using single atoms in tweezer arrays appearing recently [2, 3]. A...
In our recent work [1] we develop a method for accurate calculation and interpretation of photoionization delays in atoms and molecules measured using multiphoton interference techniques, with a particular focus on the Reconstruction of Attosecond Beating by Interference of Two-photon Transitions (RABITT).
Specifically, we investigate implications of a ``two-harmonic RABITT'' experiment...
Synopsis In this work, we demonstrate how the discrete-state-in continuum model, previously used for electron-molecule collisions, can be generalized to treat the vibronic dynamics in electron photodetachment from molecular anions. The theory is tested on models motivated by diatomic molecules, exploring phenomena known from electron-molecule collisions, such as boomerang oscillations,...
Huckans J.†², Laburthe-Tolra B.¹, Pasquiou B.¹, Pargoire Y.¹, Robert-de-Saint-Vincent M.¹
¹Université Sorbonne Paris Nord, LPL, France
² Commonwealth University of Pennsylvania, Bloomsburg, PA USA
† jhuckans@commonwealthu.edu
We are building a continuous superradiant laser on the narrow (7.5kHz) intercombination line of ⁸⁸Sr using a cold, fast (10-100 m/s) atomic beam passing through...
Precise molecular orientation is crucial for optimizing chemical reaction efficiency and enabling distortion-free measurements in the molecular frame [1,2]. We propose using Quantum Optimal Control theory to orient any molecular axes along any laboratory direction, extending previous results on ground-state molecular rotational states [3,4]. Specifically, we focus on highly rotating molecular...
The RABBITT (Reconstruction of Attosecond Beating by Interference of Two-photon Transitions) technique is a foundational tool in attosecond science, enabling the precise extraction of amplitude and phase information from photoelectron spectra. Traditional RABBITT is limited to weak infrared (IR) fields and two-photon pathways. We have generalised the framework through the RABBITT with Higher...
It is challenging to measure the real time bond formation between two atoms or molecules because of the difficulty in preparing such a system in a well-defined starting geometry. A second challenge is to measure when the reactants meet since this is determined by diffusion, a process which is not easily controlled. Previous work have overcome these difficulties by preparing the system as a...
Mixed-species Coulomb crystal operation can reduce both statistical and systematic uncertainties in optical clocks. Increased clock ion numbers provide a lower quantum projection noise limited instability and are the prerequisite for various advanced interrogation schemes, while auxiliary ions can be used for sympathetic cooling and systematic shift characterization.
We operate a clock...
The stereodynamics of the Ne(3P2) + ND3 → ND3+ /(ND_2+ + D) + e– reaction is studied in a crossed-beam experiment with aligned ammonia molecules. A sample of aligned ND3 is prepared from a supersonic expansion which is guided and polarized in a curved electrostatic guide, and aligned using a linear electric field in a selected direction. The rotational temperature and degree of alignment are...
Axion-like particles (ALPs) are well-motivated extensions to the Standard Model and could form a dark matter field that oscillates at a frequency proportional to their mass. Because the value of the ALP mass could be anywhere in the range of $10^{-22}$ to 10 eV/c$^2$, it is important to search across a broad frequency range. We present a new search for ALPs over nine orders of magnitude in...
Active atomic clocks are predicted to provide far better short-term stability and robustness against thermal fluctuations than typical feedback-based optical atomic clocks. However, continuous laser operation using an ensemble of clock atoms still remains an experimentally challenging task. We study spatial self-organization in a transversely driven ensemble of clock atoms inside an optical...
A systematical investigation of the electron-impact ionization cross sections of Sn$^+$ and Sn$^+$ ions has been performed by employing a crossed-beams technique, Single- and Double-Ionization cross sections for these ions were measured within energy ranges from the ionization threshold to 1000 eV. The study uncovers contributions from indirect ionization processes, involving the ionization or...
Emerging photo-detection applications, including ‘light-shining-through-walls’ experiments to search for new particles and interplanetary optical communications, require photodetection with extremely low dark counts and strong background rejection. Here background rejection means filtering to prevent unwanted light (back- ground light) from reaching the photon counting devices. For many...
Low-dimensional material structures—such as polyacetylenes and graphene nanoflakes—can function as tunable photonic nanoantennas, offering powerful means to tailor the optical response of nearby atomic systems. Unlike conventional mesoscopic nanoantennas, nanoflakes support a variety of optical resonances, arising from both single-particle excitations and collective modes [1]. In this work, we...
Using the experimental technique of electron-ion collision spectroscopy at the electron cooler of the heavy-ion storage ring CRYRING@ESR [1] we have measured merged-beams rate coefficients for electron-ion recombination of berylliumlike Pb$^{78+}$ ions.In the electron-ion collision energy range 12-16.5 eV, we have observed $2s2p\;(^3P_1)\,19l_j$ dielectronic recombination (DR) resonances...
A highly charged ion (HCI) captures electrons resonantly from a surface upon impact. This capture takes place into highly excited ionic states, leaving intermediate shells empty and creating a hollow atom (HA) [1,2]. The subsequent de-excitation of these HAs can be quite complex and depends strongly on whether it decays freely in vacuum or close to a target surface [3].
In this contribution,...
The electron collision experiments provide essential information on the structure of the bombarded objects. The obtained data on the cross-sections of the studied process are a valuable addition to information obtained using the optical spectroscopy technique. Such data can be found both numerically and experimentally. The measurements usually involve bombarding the selected target with a beam...
Positrons, antiparticles of electrons, have been used as versatile diagnostic tools for characterizations of a wide range of materials. In bulk systems, positrons are trapped by open-volume defects and annihilate with electrons, emitting gamma rays, which allows the non-invasive characterization of materials [1]. By recent advances in experimental techniques, positron-molecule bound states and...
We study the thermal behavior of correlations in a one-dimensional Bose gas with tunable interaction strength, crossing from weakly-repulsive to Tonks-Girardeau regime [1-2]. A reference temperature in this system is that of the hole anomaly [3], observed as a peak in the specific heat and a maximum in the chemical potential. At the anomaly temperature, the spectral states located below the...
Ultracold atom gases trapped in optical potentials offer a clean and controllable platform to realize quantum models that are difficult to implement in condensed matter systems [1]. Recent theoretical [2] and experimental [3] developments allow to create periodic sub-wavelength potentials that overcome the diffraction limit imposed by the wavelength of the used laser beams. These potentials...
Atom interferometers are high-precision sensors for acceleration, rotation and magnetic fields. Space-borne atom interferometers promise a wide range of applications from geodesy to fundamental tests of physics. Their improved sensitivity due to prolonged interrogation times benefits from the macroscopic coherence length and slow expansion rates of Bose-Einstein condensates (BECs). A limit for...
Transfer ionization (TI) is one of the processes that in the past 20 years allowed elucidating the role of target electron correlation in ion-atom collisions. A decade ago, fully differential cross sections which depend on the emitted electron momentum distribution were measured for H++He collisions at impact energies of 300 and 630 keV. This study allowed determining the dominant role of the...
The interaction of intense, short, and (near)resonant laser pulses with a two-level quantum system induces intricate dynamics, characterized by Rabi oscillations (ROs) [1] and dynamic interference (DI) [2], both of which manifest as multi-peak patterns in the photo-electron spectrum. These phenomena, central to strong-field light-matter interactions, often coexist in the Autler-Townes (AT)...
Spin mixtures of ultracold fermions are a cornerstone of quantum many-body physics, enabling superfluidity, polaron formation, and rich spin dynamics. Introducing strong, long-range dipolar forces into such mixtures promises even more exotic phases, but has been hampered by the loss of two molecules at short range. Microwave dressing can prevent the gas from the short-range collapse and induce...
We study the role of electronic correlations during high harmonic generation (HHG) in multi-electron atoms. Originally viewed as a process involving one single active electron, the influence of multi-electron effects on the HHG spectrum has lately been extensively studied (see e.g. [1, 2]). We quantify the time-dependence of electron-electron correlations on ultrafast time scales using...
Non-relativistic anyons in 1D possess generalized exchange statistics in which the exchange of two identical anyons generates a non-local phase that is governed by the spatial ordering of the particles and the statistical parameter $\alpha$. Working in the continuum, we demonstrate the existence of two distinct types of 1D anyons, namely bosonic anyons and fermionic anyons. We identify a...
First experimental observations and theoretical insights into rotational and vibrational magnetism in molecules date back more than 50 years, but a comprehensive framework for vibrationally induced magnetism remains elusive. Analogous to magnetic effects induced by molecular rotation, twofold degenerate molecular vibrations, when excited with a π/2 phase shift, induce rotational motions of the...
The relaxation processes in atomic xenon following core ionization of the 4d and 4p subshells by extreme ultraviolet (XUV) pulses from a free-electron laser (FLASH: FL26 beamline) are investigated using ion time-of-flight spectroscopy (see [1] for detailed description of the experimental setup). We compare the dynamics following ionization and Auger-Meitner decays at 90-eV photon energy, i.e.,...
Since the first demonstration of direct laser cooling of molecules, an ever-expanding set of molecular species are being investigated including heavier molecules, polyatomic molecules and “chemically interesting” molecules. While making fast beams of complex and interesting molecules is becoming routine, slowing them to rest such that they can be trapped remains a significant challenge....
We present the first observation of vibrational transitions in the [H3O]− anion, an intermediate in the anion–molecule reaction of water, H2O, and hydride, H–, using a laser-induced isotopic H/D exchange reaction action spectroscopy scheme applied to anions. The observed bands are assigned as the fundamental and first overtone of the H2O–H– vibrational stretching mode, based on anharmonic...
Arrays of optical tweezers loaded with neutral atoms have rapidly gained traction as a versatile and scalable architecture for quantum information processing. At Eindhoven University of Technology, we are developing a tweezer apparatus that allows control over single- and multi-qubit gates using the Sr clock qubit.
On the poster, we will present our recent experimental results of preparing...
