@article{20840,
  abstract     = {Probing the possibility of entanglement generation through gravity offers a path to tackle the question of whether gravitational fields possess a quantum mechanical nature. A potential realization necessitates systems with low-frequency dynamics at an optimal mass scale, for which the microgram-to-milligram range is a strong contender. Here, after refining a figure-of-merit for the problem, we present a 1-milligram torsional pendulum operating at 18 Hz. We demonstrate laser cooling its motion from room temperature to 240 microkelvins, surpassing by over 20-fold the coldest motions attained for oscillators ranging from micrograms to kilograms. We quantify and contrast the utility of the current approach with other platforms. The achieved performance and large improvement potential highlight milligram-scale torsional pendulums as a powerful platform for precision measurements relevant to future studies at the quantum-gravity interface.},
  author       = {Agafonova, Sofya and Rosello, Pere and Mekonnen, Manuel and Hosten, Onur},
  issn         = {2399-3650},
  journal      = {Communications Physics},
  publisher    = {Springer Nature},
  title        = {{One-milligram torsional pendulum toward experiments at the quantum-gravity interface}},
  doi          = {10.1038/s42005-026-02514-w},
  volume       = {9},
  year         = {2026},
}

@article{22642,
  abstract     = {Continuously operating atom-light interfaces represent a key prerequisite for steady-state quantum sensors and efficient quantum processors. Here, we demonstrate continuous accumulation of sub-Doppler-cooled atoms in a shallow intracavity dipole trap, realizing this regime. The key ingredient is a light-shift manipulation that creates spatially varying cooling parameters, enabling efficient capture and accumulation of atoms within a cavity mode. Demonstrated with rubidium atoms, a continuous flux from a source cell is funneled through the magneto-optical trap into the cavity mode, where the atoms are cooled and maintained below 10µK in steady state without time-sequenced operation. We characterize the resulting continuously maintained ensemble of millions of atoms and its collective coupling to the cavity field, establishing a route toward continuously operated cavity-QED systems and long-duration atomic and hybrid quantum sensors.},
  author       = {Gheorghita, Edward-Fulbright and Wald, Sebastian and Pupić, Andrea and Hosten, Onur},
  issn         = {2469-9934},
  journal      = {Physical Review A},
  number       = {2},
  publisher    = {American Physical Society},
  title        = {{Continuous accumulation of cold atoms in an optical cavity}},
  doi          = {10.1103/71f2-sq4p},
  volume       = {114},
  year         = {2026},
}

@misc{20842,
  abstract     = {Probing the possibility of entanglement generation through gravity offers a path to tackle the question of whether gravitational fields possess a quantum mechanical nature. A potential realization necessitates systems with low-frequency dynamics at an optimal mass scale, for which the microgram-to-milligram range is a strong contender. Here, after refining a figure-of-merit for the problem, we present a 1-milligram torsional pendulum operating at 18 Hz. We demonstrate laser cooling its motion from room temperature to 240~microkelvins, surpassing by over 20-fold the coldest motions attained for oscillators ranging from micrograms to kilograms. We quantify and contrast the utility of the current approach with other platforms. The achieved performance and large improvement potential highlight milligram-scale torsional pendulums as a powerful platform for precision measurements relevant to future studies at the quantum-gravity interface.},
  author       = {Agafonova, Sofya},
  publisher    = {Institute of Science and Technology Austria},
  title        = {{Research Data for: 'One-milligram torsional pendulum toward experiments at the quantum-gravity interface'}},
  doi          = {10.15479/AT-ISTA-20842},
  year         = {2025},
}

@article{14980,
  abstract     = {Precision sensing and manipulation of milligram-scale mechanical oscillators has attracted growing interest in the fields of table-top explorations of gravity and tests of quantum mechanics at macroscopic scales. Torsional oscillators present an opportunity in this regard due to their remarked isolation from environmental noise. For torsional motion, an effective employment of optical cavities to enhance optomechanical interactions—as already established for linear oscillators—so far faced certain challenges. Here, we propose a concept for sensing and manipulating torsional motion, where exclusively the torsional rotations of a pendulum are mapped onto the path length of a single two-mirror optical cavity. The concept inherently alleviates many limitations of previous approaches. A proof-of-principle experiment is conducted with a rigidly controlled pendulum to explore the sensing aspects of the concept and to identify practical limitations in a potential state-of-the art setup. Based on this study, we anticipate development of precision torque sensors utilizing torsional pendulums that can support sensitivities below 10−19Nm/√Hz, while the motion of the pendulums are dominated by quantum radiation pressure noise at sub-microwatts of incoming laser power. These developments will provide horizons for experiments at the interface of quantum mechanics and gravity.},
  author       = {Agafonova, Sofya and Mishra, Umang and Diorico, Fritz R and Hosten, Onur},
  issn         = {2643-1564},
  journal      = {Physical Review Research},
  number       = {1},
  publisher    = {American Physical Society},
  title        = {{Zigzag optical cavity for sensing and controlling torsional motion}},
  doi          = {10.1103/physrevresearch.6.013141},
  volume       = {6},
  year         = {2024},
}

@phdthesis{17225,
  abstract     = {This thesis describes the development of an atom interferometer designed to exploit the
advantages of utilizing quantum entanglement for enhanced precision measurements beyond
the standard quantum limit. While the project remains ongoing, significant progress has been
made.
A key contribution of this work is the development of Quantrol, an experimental control
system leveraging the ARTIQ framework. This software enables precise timing and control
without requiring prior knowledge of ARTIQ’s implementation details or coding experience.
The interface offers user friendly visual comprehension of the experimental sequence and
extended capabilities, allowing researchers to scan variables with a simple click of a mouse.
The main proposed project is to implement atom interferometric sequence with squeezed input
states inside of a dipole trap generated by a high finesse cavity. The presence of the dipole
trap allows one dimensional atomic cloud split while maintaining relatively strong confinement
in other directions.
We are currently able to trap and cool 87Rb atoms to few micro kelvin temperatures, load
them into the dipole trap and state prepare them to be used for squeezing and interferometric
sequence.},
  author       = {Li, Vyacheslav},
  issn         = {2663-337X},
  pages        = {79},
  publisher    = {Institute of Science and Technology Austria},
  title        = {{Towards a quantum entanglement enhanced atom interferomter}},
  doi          = {10.15479/at:ista:17225},
  year         = {2024},
}