A recent study by the team delved into the super and subradiant dynamics of atomic ensembles coupled to nanofibers. To achieve this, short laser pulses were used, generated by driving an electro-optic modulator with the AWG-5000 Arbitrary Waveform Generator from Active Technologies. The resulting box-car shaped optical pulses had a rise-time of less than one nanosecond, making them ideal for experiments given the shorter excited state lifetime of the atoms in the ensemble.

Riccardo Pennetta, a postdoctoral fellow at the NanoFiRe Lab, explores the multi-mode strong coupling regime of cavity quantum electrodynamics using optical nanofibers. This experimental and unexplored regime holds promise for applications in quantum information processing and the generation of non-classical states of light.

The collaborative work of R. Pennetta, M. Blaha, A. Johnson, D. Lechner, P. Schneeweiss, J. Volz, and A. Rauschenbeutel is detailed in their paper titled "Collective Radiative Dynamics of an Ensemble of Cold Atoms Coupled to an Optical Waveguide," published in Physical Review Letters (128, 073601, 2022) and recognized as an Editor's pick. The full paper is available [here].

The AWG-5000, employed in the experiments, demonstrated its capability to generate sub-nanosecond pulses down to 230 ps, reaching a voltage amplitude of 5Vpp on a 50-ohm load. With fast rise and fall times smaller than 110 ps, this instrument allows flexibility in shaping pulses for various experimental conditions.

Additionally, the PG-1072 pulse generator, used in the study, can generate sub-nanosecond pulses down to 300 ps with a voltage amplitude of 5Vpp on a 50-ohm load. Its fast repetition rate of up to 800MHz and 10ps step resolution enable precise adjustments of pulse width from 300 ps up to greater than 1 second.