7 papers
Magnetic Dipole in a Cuboidal Superconducting Trap
Francis J. Headley
We derive the exact image-dipole potential of a point dipole inside a closed cuboidal superconducting trap. The construction generalises the parallel-plate result to a geometry tha…
Detection of the Earth Tides by Diamagnetic Levitation
Tim M. Fuchs, Elliot Simcox, Michael Hawker +2
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 dist…
Rotational Quantum Tunneling of a Magnetic Dipole in a Superconducting Trap
Francis J. Headley, Fabian Müller, Emre Köse +3
We study the quantum dynamics of the rotational degree of freedom of a nano-magnet trapped in a superconducting trap. The nano-magnet is modeled as a magnetic dipole with magnetiza…
Path Integral Approach to Quantum Fisher Information
Francis J. Headley, Mahdi RouhbakhshNabati, Henry Harper-Gardner +3
We present a real-time path-integral formulation of the quantum Fisher information for dynamical parameter estimation. For pure states undergoing unitary evolution, we show that th…
Quantum Fisher Information for Entropy of Gibbs States
Francis J. Headley
We derive the quantum Fisher information for entropy estimation in a Gibbs state and show that it equals the inverse of the heat capacity, which is dual to the temperature Fisher i…
Quantum Metrology of Newton's Constant with Levitated Mechanical Systems
Francis J. Headley, Alessio Belenchia, Mauro Paternostro +1
Newton's constant is the least well-measured among the fundamental constants of Nature, and, indeed, its accurate measurement has long served an experimental challenge. Levitated m…