Related papers: Squeezed-Light Optical Magnetometry
Optically-pumped magnetometers are an important instrument for imaging biological magnetic signals without the need for cryogenic cooling. These magnetometers are presently available in the commercial market and utilize the principles of…
Magnetic resonance of sodium fluorescence is studied with varying laser intensity, duty cycle, and field strength. A magnetometer based on sodium vapor cell filled with He buffer gas is demonstrated, which uses a single amplitude-modulated…
It is known from ensemble measurements that rubidium atoms trapped in solid parahydrogen have favorable properties for quantum sensing of magnetic fields. To use a single rubidium atom as a quantum sensor requires a technique capable of…
We explore experimentally quantum non-demolition (QND) measurements of atomic spin in a hot potassium vapor in the presence of spin-exchange relaxation. We demonstrate a new technique for back-action evasion by stroboscopic modulation of…
Sensing a magnetic field with an atomic magnetometer operated in real time presents significant challenges, primarily due to sensor non-linearity, the presence of noise, and the need for one-shot estimation. To address these challenges, we…
A novel setup for the measurement of magnetic fields external to certain antiferromagnets and generally weakly remanent magnetic materials is presented. The setup features a highly sensitive Super Conducting Quantum Interference Device…
We explore the applications of spin noise spectroscopy (SNS) for detection of the spin properties of atomic ensembles in and out of equilibrium. In SNS, a linearly polarized far-detuned probe beam on passing through an ensemble of atomic…
We demonstrate magnetometry by detection of the spin state of high-density nitrogen-vacancy ensembles in diamond using optical absorption at 1042 nm. With this technique, measurement contrast, and collection efficiency can approach unity,…
Quantum sensors based on solid-state defects, in particular nitrogen-vacancy (NV) centers in diamond, enable precise measurement of magnetic fields, temperature, rotation, and electric fields. However, the sensitivity of leading NV spin…
This paper explores the sensitivity gains afforded by spin-squeezed states in atom interferometry, in particular using Bragg diffraction. We introduce a generalised input-output formalism that accurately describes realistic, non-unitary…
Spin-exchange relaxation free alkali-metal magnetometers typically operate in the regime of high optical density, presenting challenges for simple and efficient optical pumping and detection. We describe a high-sensitivity Rb magnetometer…
Squeezed light finds many important applications in quantum information science and quantum metrology, and has been produced in a variety of physical systems involving optical nonlinear processes. Here, we show how a nonlinear…
Transmission of light through an atomic sample placed between crossed polarizers in a magnetic field is jointly determined by Faraday rotation and net absorption: transmission increases with rotation and decreases with absorption. Both…
Spin noise (SN) spectroscopy measurements on delicate semiconductor spin systems, like single InGaAs quantum dots, are currently not limited by optical shot noise but rather by the electronic noise of the detection system. Here, we report a…
Cavity optomechanical (COM) sensors, enhanced by quantum squeezing or entanglement, have become powerful tools for measuring ultra-weak forces with high precision and sensitivity. However, these sensors usually rely on linear COM couplings,…
We describe an ultra-sensitive atomic magnetometer using optically-pumped potassium atoms operating in spin-exchange relaxation free (SERF) regime. We demonstrate magnetic field sensitivity of 160 aT/Hz$^{1/2}$ in a gradiometer arrangement…
We investigate the ground-state Hanle effect in alkali-metal vapor irradiating by a resonant elliptically polarized light wave. The magneto-optical resonances are observed as a change in the ellipticity parameter of the light wave…
Scanning-probe magnetometry is a valuable experimental tool to investigate magnetic phenomena at the micro- and nanoscale. We theoretically analyze the possibility of measuring magnetic fields via the electrical current flowing through…
Photoionization of a cold atomic sample offers intriguing possibilities to observe collective effects at extremely low temperatures. Irradiation of a rubidium condensate and of cold rubidium atoms within a magneto-optical trap with laser…
In this work we realize a narrow spectroscopic feature using a technique that we refer to as magnetically-induced optical transparency. A cold ensemble of $^{88}$Sr atoms interacts with a single mode of a high-finesse optical cavity via the…