arXiv subjects

C. J. Campbell

Publications and source records attributed to C. J. Campbell.

5 recordsLinked to original sources

arXiv2013

Magnetic dipole and electric quadrupole moments of the 229Th nucleus

We calculate the A and B hyperfine constants for the low-lying states of 229Th3+ using a high-precision relativistic all-order approach. By combining these calculations with measurements of the 6d and 5f hyperfine constants [C. J. Campbell et al., Phys. Rev. Lett. 106, 223001 (2011)], we determine the magnetic dipole μ=0.360(7)μ_B and the electric-quadrupole Q=3.11(6) eb moments of the 229Th nucleus. Our value for μis five times more accurate and is 22% smaller than the best previous value μ=0.46(4) μ_B [S. Gerstenkorn et al., J. Phys. (Paris) 35, 483 (1974)], while our value for Q is the same, but 2.5 times more accurate than the 2011 result. A systematic study of hyperfine structure in eight other monovalent atoms supports our claim of 2% level uncertainty for $μ$ and Q in 229Th+3.

physics.atom-ph↗

arXiv2012

Observation of the 717 nm electric quadrupole transition in triply charged thorium

We excite the 717 nm electric quadrupole 6$D_{3/2} $ $\leftrightarrow$ 7$S_{1/2}$ transition in a laser-cooled $^{232}$Th$^{3+}$ ion crystal. The transition frequency and the lifetime of the metastable 7$S_{1/2}$ level are measured to be 417 845 964(30) MHz and 0.60(7) s, respectively. We subsequently employ the 7$S_{1/2}$ level to drive the ions with nanosecond-long 269 nm laser pulses into the 7$P_{1/2}$ level. The latter is connected to the 7$S_{1/2}$ electronic level within the $^{229}$Th nuclear isomer manifold by the strongest available electron-bridge transition, forming a basis for its laser excitation.

physics.atom-ph↗

arXiv2011

Wigner Crystals of 229Th for Optical Excitation of the Nuclear Isomer

We have produced laser-cooled Wigner crystals of 229Th3+ in a linear Paul trap. The magnetic dipole (A) and electric quadrupole (B) hyperfine constants for four low-lying electronic levels and the relative isotope shifts with respect to 232Th3+ for three low-lying optical transitions are measured. Using the hyperfine B constants in conjunction with prior atomic structure calculations, a new value of the spectroscopic nuclear electric quadrupole moment Q = 3.11(16) eb is deduced. These results are a step towards optical excitation of the low-lying isomer level in the 229Th nucleus.

physics.atom-ph↗

arXiv2011

A Single-Ion Nuclear Clock for Metrology at the 19th Decimal Place

The 7.6(5) eV nuclear magnetic-dipole transition in a single 229Th3+ ion may provide the foundation for an optical clock of superb accuracy. A virtual clock transition composed of stretched states within the 5F5/2 electronic ground level of both nuclear ground and isomeric manifolds is proposed. It is shown to offer unprecedented systematic shift suppression, allowing for clock performance with a total fractional inaccuracy approaching 1 x 10^-19.

physics.atom-ph↗

arXiv2006

Dual species matter qubit entangled with light

We propose and demonstrate an atomic qubit based on a cold $^{85}$Rb-$^{87}$Rb isotopic mixture, entangled with a frequency-encoded optical qubit. The interface of an atomic qubit with a single spatial light mode, and the ability to independently address the two atomic qubit states, should provide the basic element of an interferometrically robust quantum network.

quant-ph↗