We develop a broadly applicable approach that drastically increases the ability to predict the properties of complex atoms accurately. We apply it to the case of Ir-17(+), which is of particular interest for the development of novel atomic clocks with a high sensitivity to the variation of the fine-structure constant and to dark matter searches. In general, clock transitions are weak and very difficult to identify without accurate theoretical predictions. In the case of Ir-17(+), even stronger electric-dipole (El) transitions have eluded observation despite years of effort, raising the possibility that the theoretical predictions are grossly wrong. In this work, we provide accurate predictions of the transition wavelengths and E1 transition rates for Ir-17(+). Our results explain the lack of observations of the E1 transitions and provide a pathway toward the detection of clock transitions. The computational advances we demonstrate in this work are widely applicable to most elements in the periodic table and will allow us to solve numerous problems in atomic physics, astrophysics, and plasma physics.

}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.124.163001}, author = {Cheung, C. and Safronova, M. S. and Porsev, S. G. and Kozlov, M. G. and Tupitsyn, I. I. and Bondarev, I. A.} } @article { ISI:000550674500006, title = {Calculation of higher-order corrections to the light shift of the 5s(2) S-1(0)-5s5p P-3(0)o clock transition in Cd}, journal = {Phys. Rev. A}, volume = {102}, number = {1}, year = {2020}, month = {JUL 20}, pages = {012811}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {In the recent work by Yamaguchi et al. {[}Phys. Rev. Lett. 123, 113201 (2019)] Cd was identified as an excellent candidate for a lattice clock. Here, we carried out computations needed for further clock development and made an assessment of the higher-order corrections to the light shift of the 5s(2) S-1(0) -5s5p P-3(0)o clock transition. We carried out calculations of the magnetic dipole and electric quadrupole polarizabilities and linear and circular hyperpolarizabilities of the 5s(2) S-1(0) and 5s5p P-3(0)o clock states at the magic wavelength and estimated uncertainties of these quantities. We also evaluated the second-order Zeeman clock transition frequency shift.}, issn = {1050-2947}, doi = {10.1103/PhysRevA.102.012811}, author = {Porsev, S. G. and Safronova, M. S.} } @article { ISI:000548284200010, title = {Optical clocks based on the Cf15+ and Cf17+ ions}, journal = {Phys. Rev. A}, volume = {102}, number = {1}, year = {2020}, month = {JUL 6}, pages = {012802}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {Recent experimental progress in cooling, trapping, and quantum logic spectroscopy of highly charged ions (HCIs) made HCIs accessible for high-resolution spectroscopy and precision fundamental studies. Based on these achievements, we explore a possibility to develop optical clocks using transitions between the ground and a low-lying excited state in Cf15+ and Cf17+ ions. Using a high-accuracy relativistic method of calculation, we predicted the wavelengths of clock transitions, calculated relevant atomic properties, and analyzed a number of systematic effects (such as the electric quadrupole, micromotion, and quadratic Zeeman shifts of the clock transitions) that affect the accuracy and stability of the optical clocks. We also calculated magnetic dipole hyperfine-structure constants of the clock states and the blackbody radiation shifts of the clock transitions.}, issn = {1050-2947}, doi = {10.1103/PhysRevA.102.012802}, author = {Porsev, S. G. and Safronova, I, U. and Safronova, M. S. and Schmidt, P. O. and Bondarev, I, A. and Kozlov, M. G. and Tupitsyn, I. I. and Cheung, C.} } @article { ISI:000533504100003, title = {State-Dependent Optical Lattices for the Strontium Optical Qubit}, journal = {Phys. Rev. Lett.}, volume = {124}, number = {20}, year = {2020}, month = {MAY 18}, pages = {203201}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {We demonstrate state-dependent optical lattices for the Sr optical qubit at the tune-out wavelength for its ground state. We tightly trap excited state atoms while suppressing the effect of the lattice on ground state atoms by more than 4 orders of magnitude. This highly independent control over the qubit states removes inelastic excited state collisions as the main obstacle for quantum simulation and computation schemes based on the Sr optical qubit. Our results also reveal large discrepancies in the atomic data used to calibrate the largest systematic effect of Sr optical lattice clocks.}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.124.203201}, author = {Heinz, A. and Park, A. J. and Santi, N. and Trautmann, J. and Porsev, S. G. and Safronova, M. S. and Bloch, I and Blatt, S.} } @article {ISI:000455814100005, title = {Dynamic polarizability measurements with Lu-176(+)}, journal = {Phys. Rev. A}, volume = {99}, number = {1}, year = {2019}, month = {JAN 15}, pages = {012510}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {We measure the differential polarizability of the Lu-176(+) S-1(0) <-> D-3(1) clock transition at multiple wavelengths. This experimentally characterizes the differential dynamic polarizability for frequencies up to 372 THz and allows an experimental determination of the dynamic correction to the blackbody radiation shift for the clock transition. In addition, measurements at the near resonant wavelengths of 598 and 646 nm determine the two dominant contributions to the differential dynamic polarizability below 372 THz. These additional measurements are carried out by two independent methods to verify the validity of our methodology. We also carry out a theoretical calculation of the polarizabilities using the hybrid method that combines the configuration interaction (CI) and the coupled-cluster approaches, incorporating for the first time quadratic nonlinear terms and partial triple excitations in the coupled-cluster calculations. The experimental measurements of the vertical bar < D-3(1)parallel to r parallel to P-3(J)>vertical bar matrix elements provide high-precision benchmarks for this theoretical approach.}, issn = {2469-9926}, doi = {10.1103/PhysRevA.99.012510}, author = {Arnold, K. J. and Kaewuam, R. and Tan, T. R. and Porsev, S. G. and Safronova, M. S. and Barrett, M. D.} } @article { ISI:000496923500007, title = {High-precision measurement and ab initio calculation of the (6s(2)6p(2)) P-3(0) -> P-3(2) electric-quadrupole-transition amplitude in Pb-208}, journal = {Phys. Rev. A}, volume = {100}, number = {5}, year = {2019}, month = {NOV 18}, pages = {052506}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {We have completed a measurement of the (6s(2)6p(2)) P-3(0) -> P-3(2) 939 nm electric quadrupole (E2) transition amplitude in atomic lead. Using a Faraday rotation spectroscopy technique and a sensitive polarimeter, we have measured this very weak E2 transition, and determined its amplitude to be < P-3(2) parallel to Q parallel to P-3(0)> = 8.91(9) a.u. We also present an ab initio theoretical calculation of this matrix element, determining its value to be 8.86(5) a.u., which is in excellent agreement with the experimental result. We heat a quartz vapor cell containing Pb-208 to between 800 and 940 degrees C, apply a similar to 10 G longitudinal magnetic field, and use polarization modulation and lock-in detection to measure optical rotation amplitudes of order 1 mrad with noise near 1 mu rad. We compare the Faraday rotation amplitude of the E2 transition to that of the P-3(0)-P-3(1) 1279 nm magnetic dipole (M1) transition under identical sample conditions.}, issn = {2469-9926}, doi = {10.1103/PhysRevA.100.052506}, author = {Maser, Daniel L. and Hoenig, Eli and Wang, B-Y and Rupasinghe, P. M. and Porsev, S. G. and Safronova, M. S. and Majumder, P. K.} } @article { ISI:000501342800003, title = {Measurement of the 7p P-2(3/2) state branching fractions in Ra+}, journal = {Phys. Rev. A}, volume = {100}, number = {6}, year = {2019}, month = {DEC 6}, pages = {062504}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {We report a measurement of the radium ion{\textquoteright}s 7p(2)P(3/2) state branching fractions and improved theoretical calculations. With a single laser-cooled Ra-226(+) ion we measure the P-3/2 branching fractions to the 7s(2)S(1/2) ground state 0.876 78(20), the 6d D-2(5/2) state 0.107 59(10), and the 6d D-2(3/2) state 0.015 63(21).}, issn = {2469-9926}, doi = {10.1103/PhysRevA.100.062504}, author = {Fan, M. and Holliman, C. A. and Porsev, S. G. and Safronova, M. S. and Jayich, A. M.} } @article { ISI:000441668600006, title = {Clock-related properties of Lu+}, journal = {PHYSICAL REVIEW A}, volume = {98}, number = {2}, year = {2018}, month = {AUG 14}, pages = {022509}, issn = {2469-9926}, doi = {10.1103/PhysRevA.98.022509}, author = {Porsev, S. G. and Safronova, U. I. and Safronova, M. S.} } @article { ISI:000424507800014, title = {Multipolar Polarizabilities and Hyperpolarizabilities in the Sr Optical Lattice Clock}, journal = {PHYSICAL REVIEW LETTERS}, volume = {120}, number = {6}, year = {2018}, month = {FEB 8}, pages = {063204}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.120.063204}, author = {Porsev, S. G. and Safronova, M. S. and Safronova, U. I. and Kozlov, M. G.} } @article { ISI:000427007200003, title = {New Methods for Testing Lorentz Invariance with Atomic Systems}, journal = {PHYSICAL REVIEW LETTERS}, volume = {120}, number = {10}, year = {2018}, month = {MAR 8}, pages = {103202}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.120.103202}, author = {Shaniv, R. and Ozeri, R. and Safronova, M. S. and Porsev, S. G. and Dzuba, V. A. and flambaum, v. v. and Haffner, H.} } @article { ISI:000451329500021, title = {Nobelium energy levels and hyperfine-structure constants}, journal = {PHYSICAL REVIEW A}, volume = {98}, number = {5}, year = {2018}, month = {NOV 26}, pages = {052512}, abstract = {Advances in laser spectroscopy of superheavy (Z > 100) elements enabled determination of the nuclear moments of the heaviest nuclear which required high-precision atomic calculations of the relevant hyperfine-structure (hfs) constants. Here, we calculated the hfs constants and energy levels for a number of nobelium (Z = 102) states using a hybrid approach combining linearized coupled-cluster and configuration interaction methods. We also carried out an extensive study of the No energies using the 16-electro configuration interaction method to determine the position of the 5f(13)7s(2)6d and 5f(13)7s(2)7p levels with a hole in the 5 f shell to evaluate their potential effect on the hyperfine-structure calculations of the low-lying 5f(14)7s6d and 5f(14)7s7p levels. We find that unlike the case of Yb, the mixing of the low-lying levels with filled and unfilled f shells is small and does not significantly influence their properties. The resulting hfs constants for the 5f(14)7s7p P-1(1)0 level, combined with laser-spectroscopy measurement, were used to extract nobelium nuclear properties.}, issn = {2469-9926}, doi = {10.1103/PhysRevA.98.052512}, author = {Porsev, S. G. and Safronova, M. S. and Safronova, I, U. and Dzuba, V. A. and flambaum, v. v.} } @article { ISI:000451010600006, title = {Nuclear Charge Radii of Th-229 from Isotope and Isomer Shifts}, journal = {PHYSICAL REVIEW LETTERS}, volume = {121}, number = {21}, year = {2018}, month = {NOV 21}, pages = {213001}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.121.213001}, author = {Safronova, M. S. and Porsev, S. G. and Kozlov, M. G. and Thielking, J. and Okhapkin, M. V. and Glowacki, P. and Meier, D. M. and Peik, E.} } @article { ISI:000434633000006, title = {Probing Sizes and Shapes of Nobelium Isotopes by Laser Spectroscopy}, journal = {PHYSICAL REVIEW LETTERS}, volume = {120}, number = {23}, year = {2018}, month = {JUN 8}, pages = {232503}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.120.232503}, author = {Raeder, S. and Ackermann, D. and Backe, H. and Beerwerth, R. and Berengut, J. C. and Block, M. and Borschevsky, A. and Cheal, B. and Chhetri, P. and Duellmann, Ch. E. and Dzuba, V. A. and Eliav, E. and Even, J. and Ferrer, R. and flambaum, v. v. and Fritzsche, S. and Giacoppo, F. and Goetz, S. and Hessberger, F. P. and Huyse, M. and Kaldor, U. and Kaleja, O. and Khuyagbaatar, J. and Kunz, P. and Laatiaoui, M. and Lautenschlager, F. and Lauth, W. and Mistry, A. K. and Ramirez, E. Minaya and Nazarewicz, W. and Porsev, S. G. and Safronova, M. S. and Safronova, U. I. and Schuetrumpf, B. and Van Duppen, P. and Walther, T. and Wraith, C. and Yakushev, A.} } @article { ISI:000419097100004, title = {Relativistic all-order many-body calculation of energies, wavelengths, and M1 and E2 transition rates for the 3d(n) configurations in tungsten ions}, journal = {PHYSICAL REVIEW A}, volume = {97}, number = {1}, year = {2018}, month = {JAN 3}, pages = {012502}, issn = {2469-9926}, doi = {10.1103/PhysRevA.97.012502}, author = {Safronova, M. S. and Safronova, U. I. and Porsev, S. G. and Kozlov, M. G. and Ralchenko, Yu.} } @article { ISI:000405362900007, title = {Theoretical study of the g factor and lifetime of the 6s6 p P-3(0) state of mercury}, journal = {PHYSICAL REVIEW A}, volume = {96}, number = {1}, year = {2017}, month = {JUL 13}, issn = {2469-9926}, doi = {10.1103/PhysRevA.96.012509}, author = {Porsev, S. G. and Safronova, U. I. and Safronova, M. S.} } @article { ISI:000357750100019, title = {CI-MBPT: A package of programs for relativistic atomic calculations based on a method combining configuration interaction and many-body perturbation theory}, journal = {COMPUTER PHYSICS COMMUNICATIONS}, volume = {195}, year = {2015}, month = {OCT}, pages = {199-213}, issn = {0010-4655}, doi = {10.1016/j.cpc.2015.05.007}, author = {Kozlov, M. G. and Porsev, S. G. and Safronova, M. S. and Tupitsyn, I. I.} } @article { ISI:000348775000038, title = {Michelson-Morley analogue for electrons using trapped ions to test Lorentz symmetry}, journal = {NATURE}, volume = {517}, number = {7536}, year = {2015}, month = {JAN 29}, pages = {592-U357}, issn = {0028-0836}, doi = {10.1038/nature14091}, author = {Pruttivarasin, T. and Ramm, M. and Porsev, S. G. and Tupitsyn, I. I. and Safronova, M. S. and Hohensee, M. A. and Haeffner, H.} } @article { ISI:000359984400001, title = {Observation of an unexpected negative isotope shift in Th-229(+) and its theoretical explanation}, journal = {PHYSICAL REVIEW A}, volume = {92}, number = {2}, year = {2015}, month = {AUG 25}, issn = {1050-2947}, doi = {10.1103/PhysRevA.92.020503}, author = {Okhapkin, M. V. and Meier, D. M. and Peik, E. and Safronova, M. S. and Kozlov, M. G. and Porsev, S. G.} } @article { ISI:000348766800006, title = {Atomic properties of Cd-like and Sn-like ions for the development of frequency standards and search for the variation of the fine-structure constant}, journal = {PHYSICAL REVIEW A}, volume = {90}, number = {5}, year = {2014}, month = {NOV 13}, issn = {1050-2947}, doi = {10.1103/PhysRevA.90.052509}, author = {Safronova, M. S. and Dzuba, V. A. and flambaum, v. v. and Safronova, U. I. and Porsev, S. G. and Kozlov, M. G.} } @article { ISI:000344028800006, title = {Highly charged Ag-like and In-like ions for the development of atomic clocks and the search for alpha variation}, journal = {PHYSICAL REVIEW A}, volume = {90}, number = {4}, year = {2014}, month = {OCT 31}, issn = {1050-2947}, doi = {10.1103/PhysRevA.90.042513}, author = {Safronova, M. S. and Dzuba, V. A. and flambaum, v. v. and Safronova, U. I. and Porsev, S. G. and Kozlov, M. G.} } @article { ISI:000345243200006, title = {Relativistic calculations of C-6 and C-8 coefficients for strontium dimers}, journal = {PHYSICAL REVIEW A}, volume = {90}, number = {5}, year = {2014}, month = {NOV 18}, issn = {1050-2947}, doi = {10.1103/PhysRevA.90.052715}, author = {Porsev, S. G. and Safronova, M. S. and Clark, Charles W.} } @article { ISI:000316412900002, title = {Polarizabilities, Stark shifts, and lifetimes of the In atom}, journal = {PHYSICAL REVIEW A}, volume = {87}, number = {3}, year = {2013}, month = {MAR 21}, issn = {1050-2947}, doi = {10.1103/PhysRevA.87.032513}, author = {Safronova, M. S. and Safronova, U. I. and Porsev, S. G.} } @article {2534, title = {Polarizabilities of Si2+: A benchmark test of theory and experiment}, journal = {PHYSICAL REVIEW A}, volume = {85}, year = {2012}, month = {MAY 14}, pages = {052506}, issn = {1050-2947}, doi = {10.1103/PhysRevA.85.052506}, author = {Safronova, M. S. and Porsev, S. G. and Kozlov, M. G. and Clark, Charles W.} }