Highly selective photoionization of the ytterbium atom by coherent two-photon excitation was demonstrated experimentally. The Yb atom was excited by two single-mode lasers and ionized by a time-delayed broadband laser. The isotope ratio of the ions was analyzed by a time-of-flight mass spectrometer. The ion yield and the selectivity were recorded as a function of detuning of the first exciting laser. The maximum of ion yield was observed when the laser was detuned from resonance. The selectivity of $^{168}\mathrm{Yb}$ was increased higher than 20 000 when the laser was blue-detuned to the most efficient position. Also, numerical analysis was performed to explain the experimental results. \textcopyright{} 1996 The American Physical Society.Highly selective photoionization of the ytterbium atom by coherent two-photon excitation was demonstrated experimentally. The Yb atom was excited by two single-mode lasers and ionized by a time-delayed broadband laser. The isotope ratio of the ions was analyzed by a time-of-flight mass spectrometer. The ion yield and the selectivity were recorded as a function of detuning of the first exciting laser. The maximum of ion yield was observed when the laser was detuned from resonance. The selectivity of $^{168}\mathrm{Yb}$ was increased higher than 20 000 when the laser was blue-detuned to the most efficient position. Also, numerical analysis was performed to explain the experimental results. \textcopyright{} 1996 The American Physical Society.

Physical Review AMar 1, 199610 citations

Collisions of Highly Excited Atoms

R. F. Stebbings

Advances in atomic and molecular physicsJan 1, 19798 citations

Coherent laser spectroscopy of highly charged ions using quantum logic

P. Micke, Tobias Leopold, S. A. King +6 more

Abstract Precision spectroscopy of atomic systems1 is an invaluable tool for the study of fundamental interactions and symmetries2. Recently, highly charged ions have been proposed to enable sensitive tests of physics beyond the standard model2–5 and the realization of high-accuracy atomic clocks3, 5, owing to their high sensitivity to fundamental physics and insensitivity to external perturbations, which result from the high binding energies of their outer electrons. However, the implementation of these ideas has been hindered by the low spectroscopic accuracies (of the order of parts per million) achieved so far6–8. Here we cool trapped, highly charged argon ions to the lowest temperature reported so far, and study them using coherent laser spectroscopy, achieving an increase in precision of eight orders of magnitude. We use quantum logic spectroscopy9, 10 to probe the forbidden optical transition in 40Ar13+ at a wavelength of 441 nanometres and measure its excited-state lifetime and g-factor. Our work unlocks the potential of highly charged ions as ubiquitous atomic systems for use in quantum information processing, as frequency standards and in highly sensitive tests of fundamental physics, such as searches for dark-matter candidates11 or violations of fundamental symmetries2.Abstract Precision spectroscopy of atomic systems1 is an invaluable tool for the study of fundamental interactions and symmetries2. Recently, highly charged ions have been proposed to enable sensitive tests of physics beyond the standard model2–5 and the realization of high-accuracy atomic clocks3, 5, owing to their high sensitivity to fundamental physics and insensitivity to external perturbations, which result from the high binding energies of their outer electrons. However, the implementation of these ideas has been hindered by the low spectroscopic accuracies (of the order of parts per million) achieved so far6–8. Here we cool trapped, highly charged argon ions to the lowest temperature reported so far, and study them using coherent laser spectroscopy, achieving an increase in precision of eight orders of magnitude. We use quantum logic spectroscopy9, 10 to probe the forbidden optical transition in 40Ar13+ at a wavelength of 441 nanometres and measure its excited-state lifetime and g-factor. Our work unlocks the potential of highly charged ions as ubiquitous atomic systems for use in quantum information processing, as frequency standards and in highly sensitive tests of fundamental physics, such as searches for dark-matter candidates11 or violations of fundamental symmetries2.

Jan 29, 202035 citations

Chapter Ion Trap: A Versatile Tool for the Atomic Clocks of the Future!

Raymond E. March, John F.J Todd

Since the birth of ion trapping techniques in the 1960s, physics and chemistry applications have evolved fruitfully in concert, leading to the award of one-quarter of the 1989 Nobel Prize in Physics to each of W. Paul [1] and H.G. Dehmelt [2]. Although radiofrequency ion traps were used largely for high resolution atomic spectroscopy, spin exchange experiences, and lifetimes of atomic levels [3,4], the so-called ‘QUISTOR’[5] (QUadrupole Ion STORe) opened a new vista in mass spectrometry not only for component analysis but also for studies of chemical reaction paths also. Atomic excitations that are employed in lasers and the subsequent manipulation of such atomic lasers have stimulated the realization of the huge possibilities presented by ion trapping. Laser cooling, which has permitted the attainment of extreme accuracy in atomic spectroscopy measurements, has provided the means for precise internal and external ion energy manipulation thus opening the way to novel and powerful applications, such as quantum information and atomic clocks in the optical domain [6]. In general, lasers afford quite extraordinary means for both the formation of monatomic and polyatomic ions in specic excitation states and for probing such species in excited states. Recent progress in the development of a wide range of lasers, including the advent of laser diodes, offers myriad opportunities for new kinds of investigations. Another important research direction was opened by the liberties taken with the hyperboloidal geometry of the quadrupole ion trap. Enhanced understanding of the connement properties of quadrupole ion traps allowed the exploitation of new geometries that were easier to construct, such as cylindrical ion traps that permitted ready access for experimentation, exploited new characteristics such an non-linear modes of excitation, and introduced a stretched geometry that led to improvement in mass resolution. Recently, miniaturization of cages [7] or traps on micro-chips [8] have been exploited in atomic quantum physics as well as in chemistry analysis.* It is worthy to note that the extent of progress made in each of these domains was realized due to the curiosity of researchers and their desire to learn from the results of the experiments carried out. The purpose of this chapter is to expound upon the specic topic of atomic clocks utilizing ion traps and the new challenges engaged presently for the measurement of time with extremely high precision. Today, ion atomic clocks are designed for various systems (that is, the ion-trap-oscillator ensemble) that could offer new opportunities for the design of new ion trapping applications.Since the birth of ion trapping techniques in the 1960s, physics and chemistry applications have evolved fruitfully in concert, leading to the award of one-quarter of the 1989 Nobel Prize in Physics to each of W. Paul [1] and H.G. Dehmelt [2]. Although radiofrequency ion traps were used largely for high resolution atomic spectroscopy, spin exchange experiences, and lifetimes of atomic levels [3,4], the so-called ‘QUISTOR’[5] (QUadrupole Ion STORe) opened a new vista in mass spectrometry not only for component analysis but also for studies of chemical reaction paths also. Atomic excitations that are employed in lasers and the subsequent manipulation of such atomic lasers have stimulated the realization of the huge possibilities presented by ion trapping. Laser cooling, which has permitted the attainment of extreme accuracy in atomic spectroscopy measurements, has provided the means for precise internal and external ion energy manipulation thus opening the way to novel and powerful applications, such as quantum information and atomic clocks in the optical domain [6]. In general, lasers afford quite extraordinary means for both the formation of monatomic and polyatomic ions in specic excitation states and for probing such species in excited states. Recent progress in the development of a wide range of lasers, including the advent of laser diodes, offers myriad opportunities for new kinds of investigations. Another important research direction was opened by the liberties taken with the hyperboloidal geometry of the quadrupole ion trap. Enhanced understanding of the connement properties of quadrupole ion traps allowed the exploitation of new geometries that were easier to construct, such as cylindrical ion traps that permitted ready access for experimentation, exploited new characteristics such an non-linear modes of excitation, and introduced a stretched geometry that led to improvement in mass resolution. Recently, miniaturization of cages [7] or traps on micro-chips [8] have been exploited in atomic quantum physics as well as in chemistry analysis.* It is worthy to note that the extent of progress made in each of these domains was realized due to the curiosity of researchers and their desire to learn from the results of the experiments carried out. The purpose of this chapter is to expound upon the specic topic of atomic clocks utilizing ion traps and the new challenges engaged presently for the measurement of time with extremely high precision. Today, ion atomic clocks are designed for various systems (that is, the ion-trap-oscillator ensemble) that could offer new opportunities for the design of new ion trapping applications.

CRC Press eBooksApr 19, 20160 citations

^{168}\mathrm{Yb}

was increased higher than 20 000 when the laser was blue-detuned to the most efficient position. Also, numerical analysis was performed to explain the experimental results. \textcopyright{} 1996 The American Physical Society.