MAGIS-100

Overview

The Matter-wave Atomic Gradiometer Interferometric Sensor (MAGIS-100) is a next-generation quantum sensor under construction at Fermilab. It aims to explore fundamental physics using clock atom interferometry across a 100-meter vertical baseline. The MAGIS-100 project is a collaboration between Stanford University, Fermilab, Northwestern University, and 8 other research institutions in the US and the UK.

The detector itself combines techniques demonstrated in state-of-the-art 10-meter-scale atom interferometers with the latest technological advances of the world’s best atomic clocks. It consists of a magnetically-shielded 100-meter-long vacuum tower, three "atom sources" placed along the length of the tower that produce, cool, trap, and transport clouds of ultracold Strontium atoms, and a laser room that allows laser light to be sent down from the top of the tower to perform interferometry. The experiment will be housed in a 100-meter-deep shaft at Fermilab that was constructed for a neutrino experiment many years ago.

MAGIS-100 is the first detector facility in a family of proposed experiments based on the MAGIS concept. This novel detector has many ambitious science goals, including searches for ultralight (wave-like) dark matter, tests of quantum mechanics on macroscopic time and length scales, tests of the Equivalence Principle, and paving the way for future MAGIS-style gravitational wave detectors in a yet-unexplored frequency range between 0.01 Hz and 3 Hz.

For more general-interest information on MAGIS-100, check out Fermilab's MAGIS website.

MAGIS Science Goals

The scientific ambitions of MAGIS-100 are both broad and novel. In addition to paving the way for future MAGIS-style gravitational wave detectors, MAGIS-100 itself will perform many science tasks that push current bounds on existing physics, including searches for ultralight (wave-like) dark matter, tests of quantum mechanics on macroscopic time and length scales, and tests of the Equivalence Principle.

For a more in-depth and detailed explanation of MAGIS-100's science goals, as well as the detector design and operating principles, please check out the MAGIS-100 science paper (preprint version).

Dark Matter

Astronomical and cosmological measurements have established that the energy budget of the Universe is dominated by dark energy and dark matter, but their nature remains unknown. Observational bounds permit a 10% fraction or more of the dark matter to have a mass as low as 10⁻²² eV. Dark matter in this mass range has a large number density and can be described as a classical field that oscillates at a frequency determined by the mass of the dark matter particle. This results in time-dependent effects, such as exerting accelerations on test masses, causing precession of spins, and changing the values of fundamental constants, that can be searched for using quantum sensors. These effects arise because as the classical dark matter field oscillates, the properties of the sensor (such as the quantum energy level and spin) also change, leading to time-dependent signals. With its unique sensitivity to accelerations, spin, and atomic energy levels, MAGIS-100 is sensitive to dark matter in the mass range 10⁻²² eV – 10⁻¹⁵ eV (10^-8 Hz – 10^-1 Hz) and has the potential to improve the sensitivity to any such dark matter particles with mass (frequency) by about two orders of magnitude. The plots below show MAGIS' projected sensitivity to dark matter fields that couple to (a) the electron mass and (b) the fine structure constant (right).

Quantum Mechanics

MAGIS-100 can also test quantum mechanics itself by creating delocalized, macroscopic quantum mechanical superpositions. Atomic wave packets in each interferometer can be manipulated in such a way that the two halves of each atoms' wave function are separated by distances of several meters for up to 9 seconds, substantially improving upon previous records. Comparing the interference patterns of two or more of these interferometers simultaneously can probe whether these large time and length scales affect the coherence of quantum superpositions. The detector can also potentially search for non-linear corrections to the Schrödinger equation. Moreover, MAGIS-100 may be able to measure phase shifts arising from higher order variations in the gravitational potential across the wave function, which would probe quantum mechanics in a new regime.

Gravitational Waves

The MAGIS concept takes advantage of features of both clocks and atom interferometers to allow for a single-baseline gravitational wave detector. It aims to detect gravitational waves in the scientifically rich, so-far unexplored ‘mid-band’ frequency range between 0.01 Hz and 3 Hz. This band lies below the sensitivity range of existing terrestrial interferometers (LIGO/Virgo) and above the frequency band of the planned LISA satellite detector.

Funding