Eric Paradis

Atoms and plasmas in a high-magnetic-field trap

We investigate cold rubidium plasmas in a particle trap that has the unique capability to simultaneously laser‐cool and trap neutral atoms as well as to confine plasmas in magnetic fields of about three Tesla. The atom trap is a high‐field Ioffe‐Pritchard laser trap, while the plasma trap is a Ioffe‐Penning trap that traps electrons and ions in separate wells. The observed plasma dynamics is characterized by a breathing‐mode oscillation of the positive (ionic) plasma component, which feeds back on the behavior of the negative (electron) component of the plasma. At higher densities, the observed oscillations become nonlinear. The electron component has been found to undergo rapid cooling. We further report on the recombination of magnetized plasmas into Rydberg atoms in transient traps and quasi‐steady‐state traps. In transient traps, large numbers of recombined Rydberg atoms in high‐lying states are observed. In quasi‐steady‐state traps, the measured numbers of recombined atoms are lower and the binding e...

A vapor-cell atomic sensor for radio-frequency field detection using a polarization-selective field enhancement resonator

We present a hybrid atomic sensor that realizes radio-frequency electric field detection with intrinsic field amplification and polarization selectivity for robust high-sensitivity field measurement. The hybrid sensor incorporates a passive resonator element integrated with an atomic vapor cell that provides amplification and polarization selectivity for detection of incident radio-frequency fields. The amplified intra-cavity radio-frequency field is measured by atoms using a quantum-optical readout of AC level shifts of field-sensitive atomic Rydberg states. In our experimental demonstration, we employ a split field-enhancement resonator embedded in a rubidium vapor cell to amplify and detect C-band radio-frequency fields. We observe a field amplification equivalent to a 24 dB gain in intensity sensitivity. The spatial profile of the resonant field mode inside the field-enhancement cavity is characterized. The resonant field modes only couple with a well-defined polarization component of the incident field, allowing us to measure the polarization of the incident field in a robust fashion. Measured field enhancement factors, polarization-selectivity performance, and field distributions for the hybrid sensor are in good agreement with simulations. Applications of hybrid atomic sensors in ultra-weak radio-frequency detection and advanced measurement capabilities are discussed.We present a hybrid atomic sensor that realizes radio-frequency electric field detection with intrinsic field enhancement and polarization selectivity for robust high-sensitivity field measurement. The sensor incorporates a passive resonator element integrated with an atomic vapor cell that provides enhancement and polarization selectivity of incident radio-frequency fields. The enhanced intra-cavity radio-frequency field is measured by atoms using a quantum-optical readout of AC level shifts of field-sensitive atomic Rydberg states. In our demonstration, we employ a split field-enhancement resonator embedded in a rubidium vapor cell to enhance and detect C-band radio-frequency fields. We observe a field enhancement equivalent to a 24u2009dB gain in intensity sensitivity. The spatial profile of the resonant field mode inside the field-enhancement cavity is characterized and robust polarization measurement of the incident field is demonstrated. The measured performance metrics of the sensor are in good agreement with simulations. Applications of such atomic sensors in ultra-weak radio-frequency detection and advanced measurement capabilities are discussed.We present a hybrid atomic sensor that realizes radio-frequency electric field detection with intrinsic field enhancement and polarization selectivity for robust high-sensitivity field measurement. The sensor incorporates a passive resonator element integrated with an atomic vapor cell that provides enhancement and polarization selectivity of incident radio-frequency fields. The enhanced intra-cavity radio-frequency field is measured by atoms using a quantum-optical readout of AC level shifts of field-sensitive atomic Rydberg states. In our demonstration, we employ a split field-enhancement resonator embedded in a rubidium vapor cell to enhance and detect C-band radio-frequency fields. We observe a field enhancement equivalent to a 24u2009dB gain in intensity sensitivity. The spatial profile of the resonant field mode inside the field-enhancement cavity is characterized and robust polarization measurement of the incident field is demonstrated. The measured performance metrics of the sensor are in good agreeme...