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Hyperfine structure (HFS) of atomic energy levels arises due to interactionsof atomic electrons with a hierarchy of nuclear multipole moments, includingmagnetic dipole, electric quadrupole and higher rank moments. Recently, adetermination of the magnetic octupole moment of the $^{173}\mathrm{Yb}$nucleus was reported from HFS measurements in neutral ${}^{173}\mathrm{Yb}$[PRA 87, 012512 (2013)], and is four orders of magnitude larger than thenuclear theory prediction. Considering this substantial discrepancy between thespectroscopically extracted value and nuclear theory, here we propose to use analternative system to resolve this tension, a singly charged ion of the same$^{173}\mathrm{Yb}$ isotope. Utilizing the substantial suite of tools developedaround $\mathrm{Yb}^+$ for quantum information applications, we propose toextract nuclear octupole and hexadecapole moments from measuring hyperfinesplittings in the extremely long lived first excited state($4f^{13}(^2\!F^{o})6s^2$, $J=7/2$) of $^{173}\mathrm{Yb}^+$. We presentresults of atomic structure calculations in support of the proposedmeasurements.

Hyperfine structure (HFS) of atomic energy levels arises due to interactionsof atomic electrons with a hierarchy of nuclear multipole moments, includingmagnetic dipole, electric quadrupole and higher rank moments. Recently, adetermination of the magnetic octupole moment of the $^{173}\mathrm{Yb}$nucleus was reported from HFS measurements in neutral ${}^{173}\mathrm{Yb}$[PRA 87, 012512 (2013)], and is four orders of magnitude larger than thenuclear theory prediction. Considering this substantial discrepancy between thespectroscopically extracted value and nuclear theory, here we propose to use analternative system to resolve this tension, a singly charged ion of the same$^{173}\mathrm{Yb}$ isotope. Utilizing the substantial suite of tools developedaround $\mathrm{Yb}^+$ for quantum information applications, we propose toextract nuclear octupole and hexadecapole moments from measuring hyperfinesplittings in the extremely long lived first excited state($4f^{13}(^2\!F^{o})6s^2$, $J=7/2$) of $^{173}\mathrm{Yb}^+$. We presentresults of atomic structure calculations in support of the proposedmeasurements.

We demonstrate the use of a frequency-doubled optical frequency comb to load, cool, and crystallize trapped atomic ions as an alternative to ultraviolet (UV) or even deep UV continuous-wave lasers. We find that the Doppler shift from the atom's oscillation in the trap, driven by the blue-detuned comb teeth, introduces additional cooling and amplification which gives rise to steady-state phonon lasing of the ion's harmonic motion in the trap. The phonon laser's gain saturation keeps the optical frequency comb from continually adding energy without bound. This protection allows us to demonstrate loading and crystallization of hot ions directly with the comb, eliminating the need for a continuous-wave cooling laser, a technique that is extendable to the deep UV.

We crystallize up to 15 ^{40}Ca^{+} ions in a ring with a microfabricated silicon surface Paul trap. Delocalization of the Doppler laser-cooled ions shows that the translational symmetry of the ion ring is preserved at millikelvin temperatures. By characterizing the collective motion of the ion crystals, we identify homogeneous electric fields as the dominant symmetry-breaking mechanism at this energy scale. With increasing ion numbers, such detrimental effects are reduced. We predict that, with only a ten-ion ring, uncompensated homogeneous fields will not break the translational symmetry of the rotational ground state. This experiment opens a door towards studying quantum many-body physics with translational symmetry at the single-particle level.

We crystallize up to 15 40Ca+ ions in a ring with a microfabricated silicon surface Paul trap. Delocalization of the Doppler laser-cooled ions shows that the translational symmetry of the ion ring is preserved at millikelvin temperatures. By characterizing the collective motion of the ion crystals, we identify homogeneous electric fields as the dominant symmetry-breaking mechanism at this energy scale. With increasing ion numbers, such detrimental effects are reduced. We predict that, with only a ten-ion ring, uncompensated homogeneous fields will not break the translational symmetry of the rotational ground state. This experiment opens a door towards studying quantum many-body physics with translational symmetry at the single-particle level. [ABSTRACT FROM AUTHOR]

We present a method for achieving high fidelity state preparation and measurement (SPAM) using trapped ion hyperfine qubits with nuclear spins higher than I=1/2. The ground states of these higher nuclear spin isotopes do not afford a simple frequency-selective state preparation scheme. We circumvent this limitation by stroboscopically driving strong and weak transitions, blending fast optical pumping using dipole transitions, and narrow microwave or optical quadrupole transitions. We demonstrate this method with the I=3/2 isotope ^{137}Ba^{+} to achieve a SPAM infidelity of (9.0±1.3)×10^{-5} (-40.5±0.6  dB), facilitating the use of a wider range of ion isotopes with favorable wavelengths and masses for quantum computation.