arXiv subjects

Rene Rugango

Publications and source records attributed to Rene Rugango.

4 recordsLinked to original sources

arXiv2017

Reassigning the CaH$^+$ 1$^{1}\Sigma\rightarrow$ 2$^{1}\Sigma$ vibronic transition with CaD$^+$

We observe vibronic transitions in CaD$^+$ between the 1$^{1}\Sigma$ and 2$^{1}\Sigma$ electronic states by resonance enhanced multiphoton photodissociation spectroscopy in a Coulomb crystal. The vibronic transitions are compared with previous measurements on CaH$^+$. The result is a revised assignment of the CaH$^+$ vibronic levels and a disagreement with CASPT2 theoretical calculations by approximately 700 cm$^{-1}$.

physics.atom-ph↗

arXiv2016

Trapping and Sympathetic Cooling of Boron Ions

We demonstrate the trapping and sympathetic cooling of B$^{+}$ ions in a Coulomb crystal of laser-cooled Ca$^{+}$, We non-destructively confirm the presence of the both B$^+$ isotopes by resonant excitation of the secular motion. The B$^{+}$ ions are loaded by ablation of boron and the secular excitation spectrum also reveals features consistent with ions of the form B$_{n}^{+}$.

physics.atom-ph↗

arXiv2016

Vibronic spectroscopy of sympathetically cooled CaH$^+$

We report the measurement of the 1$^{1}\Sigma\longrightarrow$ 2$^{1}\Sigma$ transition of CaH$^+$ by resonance-enhanced photodissociation of CaH$^+$ that is co-trapped with laser-cooled Ca$^+$ . We observe four resonances that we assign to transitions from the vibrational $v$=0 ground state to the $v'$=1-4 excited states based on theoretical predictions. A simple theoretical model that assumes instantaneous dissociation after resonant excitation yield results in good agreement with the observed spectral features except for the unobserved $v'$=0 peak. The resolution of our experiment is limited by the mode-locked excitation laser, but this survey spectroscopy enables future rotationally resolved studies with applications in astrochemistry and precision measurement.

physics.atom-ph↗

arXiv2014

Sympathetic cooling of molecular ion motion to the ground state

We demonstrate sympathetic sideband cooling of a $^{40}$CaH$^{+}$ molecular ion co-trapped with a $^{40}$Ca$^{+}$ atomic ion in a linear Paul trap. Both axial modes of the two-ion chain are simultaneously cooled to near the ground state of motion. The center of mass mode is cooled to an average quanta of harmonic motion $\overline{n}_{\mathrm{COM}} = 0.13 \pm 0.03$, corresponding to a temperature of $12.47 \pm 0.03 ~\mu$K. The breathing mode is cooled to $\overline{n}_{\mathrm{BM}} = 0.05 \pm 0.02$, corresponding to a temperature of $15.36 \pm 0.01~\mu$K.

physics.atom-ph↗