Implementing an electronic sideband offset lock for precision spectroscopy in radium

Abstract

We demonstrate laser frequency stabilization with at least 6 GHz of offset tunability using an in-phase/quadrature (IQ) modulator to generate electronic sidebands (ESB) on a titanium sapphire laser at 714 nm and we apply this technique to the precision spectroscopy of ${}^{226}$Ra, and ${}^{225}$Ra. By locking the laser to a single resonance of a high finesse optical cavity and adjusting the lock offset, we determine the frequency difference between the magneto-optical trap (MOT) transitions in the two isotopes to be $2630.0\pm 0.3$ MHz, a factor of 29 more precise than the previously available data. Using the known value of the hyperfine splitting of the ${}^3{P}_1$ level, we calculate the isotope shift for the ${}^1{S}_0$ to ${}^3{P}_1$ transition to be $2267.0\pm 2.2$ MHz, which is a factor of 8 more precise than the best available value. Our technique could be applied to countless other atomic systems to provide unprecedented precision in isotope shift spectroscopy and other relative frequency comparisons.

References in corpus (9)

• Electric Dipole Moments of the Atoms, Molecules, Nuclei and Particles
• Nuclear time-reversal violation and the Schiff moment of 225Ra
• Collective T- and P- Odd Electromagnetic Moments in Nuclei with Octupole Deformations
• Improved limit on the ${}^{225}$Ra electric dipole moment
• Calculation of P,T-odd electric dipole moments for diamagnetic atoms ${}^{129}$Xe, ${}^{171}$Yb, ${}^{199}$Hg, ${}^{211}$Rn, and ${}^{225}$Ra
• Hyperfine structure of the metastable 3P2 state of alkaline earth atoms as an accurate probe of nuclear magnetic octupole moments
• Robust laser frequency stabilization by serrodyne modulation
• Electric dipole moment of ${}^{225}$Ra due to P- and T-violating weak interactions
• Efficient, Tightly-Confined Trapping of 226Ra

Cited by in corpus (3)

• A practical guide to feedback control for Pound-Drever-Hall laser linewidth narrowing
• Errors in PDH offset locking due to spurious spectral features
• Offset sideband locking to iodine for laser cooling on the ${}^1{\mathrm{S}}_0\to {}^3{\mathrm{P}}_1$ transition of ${}^{171}\mathrm{Yb}$