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A simple empirical relationship has been proposed to estimate the bulk modulus (B) of ternary chalcopyrite structure solids of I-II-VI, II-IV-V type from the electronegativities of the constituent atoms and the principal quantum number of the compounds. The current relationship is based on a model of chemical bonding. The chemical bonding of constituent atoms of compounds is determined by electronegativity and principal quantum number. Chemical bonding is the beginning point for a compound's stability, which is based on the minimal energy principle. The nature of material bonding was correlated with ground state properties such as bulk modulus in this study. The bonding of ternary chalcopyrite structure solids is well explained by the combination of electronegativity and main quantum number. These two metrics are a good indicator of chalcopyrite structure solids' structural stability. The computed bulk modulus values are found to be in good agreement with known values, and a comparison of our current results to those in the literature is also provided. In the present study, it is found that electronegativity and average principal quantum number which expresses the nature of bonding in chalcopyrites.

A complete set of spectroscopic data is indispensable when using Rydberg states of trapped ions for quantum information processing. We carried out Rydberg series spectroscopy for $n{S}_{1/2}$ states with $38\ensuremath{\le}n\ensuremath{\le}65$ and for $n{D}_{5/2}$ states with $37\ensuremath{\le}n\ensuremath{\le}50$ on a single trapped $^{40}{\mathrm{Ca}}^{+}$ ion. We determined the ionization energy of 2 870 575.582(15) GHz, 60 times more accurately as compared to the accepted value and contradicting it by 7.5 standard deviations. We confirm quantum defect values of ${\ensuremath{\delta}}_{{S}_{1/2}}=1.802\text{ }995(5)$ and ${\ensuremath{\delta}}_{{D}_{5/2}}=0.626\text{ }888(9)$ for $n{S}_{1/2}$ and $n{D}_{5/2}$ states, respectively, which allow for unambiguous addressing of Rydberg levels of ${\mathrm{Ca}}^{+}$ ions. Our measurements confirm Rydberg ion scaling properties, e.g., for blackbody induced ionization, linewidths and excitation strengths.

Two-dimensional atomic layers composed of metallic atoms with a high principal quantum number in valence shells are promising materials for applications in state-of-the-art magnetic devices due to the presence of a strong spin-orbit coupling. In this work we experimentally explored the effects of triggering perpendicular magnetic anisotropy (PMA) of ferromagnetic (FM) films by applying a series of $6p$-Pb, Bi and $4d$-Pd (reference) atomic layers with high-level atomic orbital and low-level lattice strain. Our research indicates that, compared with Pd atoms, Pb and Bi atoms can produce higher-strength PMA on adjacent FM films through orbital hybridization at the interface. Moreover, we demonstrate that the PMA induced by Pb and Bi atoms is highly sensitive to the ordering degree of the wetting layer which is determined by the interplay of surface free, cohesive, and strain energies within the grown materials; the Pb(Bi) atoms added on the wetting layer can enhance the PMA of the adjacent FM film only when the wetting layer maintains an ordered structure. This work clarifies the critical interface effects of $6p$-HMs on the FM layer, thus providing important clues to increase control over the spin-orbit interaction engendered by HMs through the interface.

Extended Hubbard models have proven to bear novel quantum states, but their experimental realization remains challenging. In this work we propose to use bosonic quantum gases dressed with molecular bound states in Rydberg interaction potentials for the observation of these quantum states. We study the molecular Rabi coupling with respect to principal quantum number and trapping frequency of the ground state atoms for various molecular potentials of Rubidium and Potassium, and the hereby resulting dressed interaction strength. Additionally, we propose a two-color excitation scheme which significantly increases the dressed interaction and cancels AC Stark shifts limiting the atomic motion in the itinerant regime. We study the various equilibrium phases of the corresponding extended Bose-Hubbard model by means of the Cluster Gutzwiller approach and perform time evolution simulations via the Lindblad master equation. We find a supersolid phase by slowly ramping the molecular Rabi coupling of an initially prepared superfluid and discuss the role of dissipation., Comment: 11 pages, 7 figures

In this work, we have experimentally and theoretically investigated the high-lying Rydberg state excitation for noble gas atoms subject to an intense near-infrared laser field. To obtain the signal of these high-lying Rydberg atoms which are further ionized by a constant electric field $({F}_{c})$, coincident detection of the photoelectrons and photoions with well-chosen arrival times is performed. Based on a fitting to the time dependence of the coincidently measured photofragment yields with a semiempirical formula, we can extract a principal quantum number distribution (PQND) of the population of the excited states in a range closely related to the strength of ${F}_{c}$. The extracted valid PQND is in qualitative agreement with a semiclassical model calculation. Our work thus provides a method to extract the PQND and study the ultrafast high-lying Rydberg state excitation.

Atoms with principal quantum number smaller than 2 are traditionally regarded to be nonmagnetic, but recent appealing advances in the understanding of ferromagnetism in materials such as graphene nanoribbons with zigzag edges and triangular graphene nanoflakes pave a novel way to investigate magnetism in materials merely with $s$ and $p$ orbitals. Opening the $p$ shell turns out to be essential for the production of unpaired electrons, and the normal chemical treatment is to modify the molecules with various atoms and groups such as hydrogen. In this paper, we combine first-principles calculations with the Hubbard model to investigate magnetic properties in hydrogenated ${\mathrm{C}}_{60}$ (${\mathrm{C}}_{60}{\mathrm{H}}_{n}$). For the enumerated ${\mathrm{C}}_{60}{\mathrm{H}}_{2}$ structures, there are nine configurations with ferromagnetic ground states and one configuration with an antiferromagnetic ground state. We have proposed a pair magnetic interaction model to predict the magnetic order, as well as a general rule to screen the maximum local magnetic moments for given $n$. When $n=3$ and 4, our model can give a good prediction of magnetic order, which is confirmed by the first-principles calculations. We find that the maximum number of unpaired electrons in ${\mathrm{C}}_{60}{\mathrm{H}}_{n}$ is smaller than the number of hydrogen atoms when $n\ensuremath{\ge}6$.

Nonlinear optical studies of the yellow and green exciton series in ${\mathrm{Cu}}_{2}\mathrm{O}$ have been reported for more than 40 years. Because of the band structure (the two highest even-parity valence and lowest conduction bands), the $S$ excitons of the two lowest exciton series are dipole-forbidden for one-photon absorption and thus dipole-allowed for two-photon absorption. There is an odd-parity higher conduction band that leads with the two even-parity valence bands to the blue and violet exciton series. We report on second-harmonic generation (SHG) of the blue exciton series. The odd-parity $S$-exciton SHG is due to a dipole-quadrupole excitation and a dipole emission process. Because of their high oscillator strength density, polariton effects have to be taken into account, since resonances might be shifted to higher energies by up to $10\phantom{\rule{4pt}{0ex}}\mathrm{me}\mathrm{V}$ compared to the transverse exciton energies. The polariton dispersion for the blue excitons up to $n=4$ is calculated and compared to the experimental results. In magnetic fields up to $10\phantom{\rule{4pt}{0ex}}\mathrm{T}$ applied in a Voigt configuration ($\mathbf{B}\ensuremath{\perp}\mathbf{k}$), SHG of $S$ excitons by a dipole-dipole excitation is observed, which is due to the admixture of dipole-dipole excited $P$ excitons by the effective electric field from the magneto-Stark effect (MSE). From the analysis of the diamagnetic shift and the MSE interaction of the three-level system of $1S, 2S$, and $2P$ excitons, we derive experimental results for the ratio $\ensuremath{\langle}{r}_{n,l}^{2}\ensuremath{\rangle}/{\ensuremath{\mu}}_{X}$ between the average of radius squared for the three states and the reduced exciton mass. For higher principal quantum number states, we observe magnetoexcitons up to $n=8$. We analyze their magnetic field dependence and derive the electron effective-mass values for the crystalline orientations [111], $[1\overline{1}0]$, and [001].

High-lying Rydberg states of Mott-Wannier excitons are receiving considerable interest due to the possibility of adding long-range interactions to the physics of exciton-polaritons. Here, we study Rydberg excitation in bulk synthetic cuprous oxide grown by the optical float zone technique and compare the result with natural samples. X-ray characterization confirms both materials are mostly single crystal, and mid-infrared transmission spectroscopy revealed little difference between synthetic and natural material. The synthetic samples show principal quantum numbers up to $n=10$, exhibit additional absorption lines, plus enhanced spatial broadening and spatial inhomogeneity. Room temperature and cryogenic photoluminescence measurements reveal a significant excess of copper vacancies in the synthetic material. These measurements provide a route towards achieving \mbox{high-$n$} excitons in synthetic crystals, opening a route to scalable quantum devices., 10 pages, 8 figures, submitted to Phys. Rev. Materials

This paper deals with a new approach in the formation of periods in the Mendeleevs Periodic Table. Using a newly suggested formula and newly suggested quantum states for the external electron shells of atoms of chemical elements, the author proposed the reconfiguration of periods in the Mendeleevs table. The reducing of the number of periods in the table is assumed, andthe material represented in the paper proves it.The following order of formation of electron layers is suggested: the principle quantum number (n), followed by the quantum state of electrons (first and second) which constitute the electron configurations of subperiods, and only after that - the remaining quantum orbitals(s, d, f, and p). &nbsp

From electronegativity and principal quantum number of II-VI, III-V semiconductors, a general empirical formula for calculating bulk modulus (B) and microhardness (H) was discovered. Constant C1, which appears in the expression of bulk modulus, as well as constants C2 and C3, which appear in the expression of microhardness and the exponent M, have the following values. The numerical values of C1,C2, C3 and M are respectively 206.6, 8.234, 1.291, -1.10 for II-VI 72.4, 31.87, 7.592, -0.95 for III-V semiconductors. The chemical bonding behaviour of constituent atoms in these semiconductors can be accurately reflected by both electro-negativity and principal quantum number. The measured bulk modulus and microhardness values are very similar to the reported results. The results of this research would aid in the development of new semiconductor materials as well as the investigation of their mechanical properties.

Exploring the dynamics of inelastic and reactive collisions on the quantum level is a fundamental goal in quantum chemistry. Such collisions are of particular importance in connection with Rydberg atoms in dense environments since they may considerably influence both the lifetime and the quantum state of the scattered Rydberg atoms. Here, we report on the study of state-changing collisions between Rydberg atoms and ground state atoms. We employ high-resolution momentum spectroscopy to identify the final states. In contrast to previous studies, we find that the outcome of such collisions is not limited to a single hydrogenic manifold. We observe a redistribution of population over a wide range of final states. We also find that even the decay to states with the same angular momentum quantum number as the initial state, but different principal quantum number is possible. We model the underlying physical process in the framework of a short-lived Rydberg quasi-molecular complex, where a charge exchange process gives rise to an oscillating electric field that causes transitions within the Rydberg manifold. The distribution of final states shows a diffusive-like behavior., Here, the authors discuss state-changing inelastic collisions between rubidium Rydberg and ground state atoms. They employ high-resolution magneto-optical trap recoil-ion momentum spectroscopy to measure the distribution of the final states.

Monolayer (1L) MoSe 2 is a two-dimensional direct-gap semiconductor. Due to the low dimensionality and reduced dielectric screening, careers experience stronger Coulombic interaction than that in conventional bulk materials, which results in excitonic binding energy as large as hundreds of meV [1] . Recent hBN encapsulation technique enabled one to observe s-series excitons with the principal quantum number of up to n=4 [2] . In that report, their energy positions are analyzed using the Keldysh potential model [3] , which describes Coulombic interaction in thin materials. However, nonnegligible additional factors such as Berry curvature [4] also affect excitonic structure. For example, p-series excitons are sensitive to Berry curvature contribution due to their finite angular momenta. To disentangle these effects, it is important to access optically dark 2p excitons. So far, no direct observation of the 2p exciton has been reported for hBN-encapsulated sample and only the indirect estimation of the energy separation between 2s and 2p excitons was made by the optical Stark effect [5] .