arXiv subjects

Elliot Simcox

Publications and source records attributed to Elliot Simcox.

5 recordsLinked to original sources

arXiv2026

Detection of the Earth Tides by Diamagnetic Levitation

The detection of mass distributions and mass transport via gravity mapping is a key geophysical tool for understanding the structure and dynamics of the earth. Changes in mass distribution, driven by natural processes and human activity (e.g., extraction of oil, gas, and minerals), contribute to observable phenomena such as sea-level rise (3 mm per year), increased flooding, landslides, and ice mass loss (hundreds of giga-tons per year). These processes generate gravity variations detectable by gravimeters and gradiometers on ground and in space. Current instruments achieve sensitivities of 10-100 micro-GAL per square root of Hz and enable applications including hydrocarbon exploration, volcanic monitoring, and subsurface detection. They also measure Earth tides (100-300 micro-GAL amplitude), requiring long-term stability over days. However, existing systems are limited by size (more than 8 kg) and cost (more than 100,000 USD), restricting widespread deployment. Here we demonstrate a levitated mechanical sensor (LOMS) with a demonstrated sensitivity of 18 micro-GAL, a large dynamical range, and an integration time of 6 s, with an expected sensitivity of smaller than 200 nano-GAL per square root of Hz in a volume of only a few cubic cm. We resolve earth tide signals, demonstrating stability comparable to state-of-the-art instruments. Unlike conventional accelerometers (micro-g sensitivity, low stability), our device operates as a true gravimeter. Its compact size and low projected cost enable scalable deployment, including drone-based surveys (10-100 m altitude), distributed sensor networks, and multipixel gravity imaging arrays. This platform enables high-resolution, cost-effective gravity mapping with potential for large-scale geophysical monitoring.

physics.geo-ph↗

arXiv2025

Macroscopic Quantum Resonators Path Finder (MAQRO-PF) White Paper

Optically levitated particles are used in a wide range of experiments to explore both fundamental physics and to act as sensors to a variety of external forces. One field of particular interest that these particles can be used to investigate is quantum mechanics. Previous research has yet to set an absolute upper bound on the size of objects that can be prepared in a quantum superposition. Exploring this limit involves allowing ever-larger objects to freely and coherently evolve to assess if their behaviour matches quantum or classical theoretical predictions. However, the long free evolution times required for these behaviours to be visible result in the experiments being gravitationally limited. Space based platforms therefore become the next key step in these investigations. In this white paper, we shall discuss our proposal for an optical levitation experiment in space that will explore the fundamental upper size limits of quantum mechanics. We shall cover the scientific motivation behind these investigations, then summarize the current status of our designs for the satellite. We will then review the aspects of the payload that require further development, then summarize the current estimates of the payload's requirements.

quant-ph↗

arXiv2025

Enhancement of the effects due to the Schr\"odinger-Newton equation

The Schr\"odinger-Newton (SN) equation introduces a nonlinear self-gravitational term to the standard Schr\"odinger equation, offering a paradigmatic model for semiclassical gravity. However, the small deviations it predicts from standard quantum mechanics pose significant experimental challenges. We propose a novel method to amplify such deviations through periodic modulation of the trapping frequency in a levitated mechanical oscillator. We identify specific regimes where the SN-induced effects on the dynamics of second moments are significantly enhanced-by up to six orders of magnitude compared to unmodulated setups. We show that this protocol remains feasible within current magnetic levitation technologies and enables distinguishability between standard and SN dynamics using measurable quantities such as the position variance. Our results pave the way for a viable experimental test of the SN equation, offering a new route to probe the interface between quantum mechanics and gravity.

quant-ph↗

arXiv2025

An experimental platform for levitated mechanics in space

Conducting levitated mechanical experiments in extreme conditions has long been the aim of researchers, as it allows for the investigation of new fundamental physics phenomena. One of the great frontiers has been sending these experiments into the micro-g environment of space, with multiple proposals calling for such a platform. At the same time, levitated sensors have demonstrated a high sensitivity to external stimuli which will only improve in low-vibrational conditions. conditions This paper describes the development of a technology demonstrator for optical and magnetic trapping experiments in space. Our payload represents the first concrete step towards future missions with aims of probing fundamental physical questions: matter-wave interferometry of nanoparticles to probe the limits of macroscopic quantum mechanics, detection of Dark Matter candidates and gravitational waves to test physics beyond the Standard Model, and accelerometry for Earth-observation.

physics.ins-det↗

arXiv2023

Linear cooling of a levitated micromagnetic cylinder by vibration

We report feedback cooling of translational and librational degrees of freedom of a levitated micromagnet cylinder, utilizing a piezoelectric actuator to apply linear feedback to high-Q mechanical modes. The normal modes are measured with a superconducting pick-up coil coupled to a DC SQUID, and phase information is fed back to the piezoelectric actuator to feedback cool a center-of-mass mode to $\sim$7 K, and a librational mode to $830 \pm 200$ mK. Q-factors of $1.0 \times 10^7$ are evaluated for the center-of-mass mode. We find that it is plausible to achieve ground state cooling of the center-of-mass mode by introducing vibration isolation, optimizing the geometry of the pick-up coil to focus on the specific mode of interest and utilizing a state-of-the-art SQUID for detection.

quant-ph↗