Date Jul 29, 2019, 2:00 pm – 2:00 pm Location Jadwin 303 Share on X Share on Facebook Share on LinkedIn Speaker Tao Wang Affiliation Berkeley Details Event Description Dark matter and dark energy are the most abundant yet mysterious substances in the Universe. Axions and axion-like particles (ALP) have emerged as theoretically well-motivated dark-matter candidates. Ultrahigh sensitivity magnetometers play important roles in dark matter searches. Here we demonstrate a Spin-Exchange Relaxation-Free (SERF) magnetometer/co-magnetometer useful for detecting axion/ALP induced ac-EDMs (electric dipole moment) in ferroelectric samples or ALP induced pseudo-magnetic fields. Even greater sensitivity could be achieved with a ferromagnetic precessing needle magnetometer, whose sensitivity could surpass the standard quantum limit. Levitation of a micron-scale ferromagnetic particle above a superconductor is a possible method of near frictionless suspension enabling observation of ferromagnetic particle precession and ultra-sensitive torque measurements. We experimentally investigate the dynamics of a micron-scale ferromagnetic particle levitated above a superconducting niobium surface.Dark matter and dark energy are the most abundant yet mysterious substances in the Universe. Axions and axion-like particles (ALP) have emerged as theoretically well-motivated dark-matter candidates. Ultrahigh sensitivity magnetometers play important roles in dark matter searches. Here we demonstrate a Spin-Exchange Relaxation-Free (SERF) magnetometer/co-magnetometer useful for detecting axion/ALP induced ac-EDMs (electric dipole moment) in ferroelectric samples or ALP induced pseudo-magnetic fields. Even greater sensitivity could be achieved with a ferromagnetic precessing needle magnetometer, whose sensitivity could surpass the standard quantum limit. Levitation of a micron-scale ferromagnetic particle above a superconductor is a possible method of near frictionless suspension enabling observation of ferromagnetic particle precession and ultra-sensitive torque measurements. We experimentally investigate the dynamics of a micron-scale ferromagnetic particle levitated above a superconducting niobium surface.