Related papers: High Bandwidth Atomic Magnetometery with Continuou…
We operate a nitrogen vacancy (NV-) diamond magnetometer at ambient temperatures and study the dependence of its bandwidth on experimental parameters including optical and microwave excitation powers. We introduce an analytical theory that…
We demonstrate an optical quantum nondemolition (QND) interaction gate with a bandwidth of about 100 MHz. Employing this gate, we are able to perform QND measurements in real time on randomly fluctuating signals. Our QND gate relies upon…
We address the estimation of the magnetic field B acting on an ensemble of atoms with total spin J subjected to collective transverse noise. By preparing an initial spin coherent state, for any measurement performed after the evolution, the…
We present a single-beam atomic magnetometer operating at room temperature for the measurement of ac magnetic fields. The magnetometer functions in the non-linear regime of magneto-optical rotation of $^{85}$Rb atomic vapour. We demonstrate…
Quantum sensing is a fundamental building block of modern technology that employs quantum resources and creates new opportunities for precision measurements. However, previous methods usually have a common assumption that detection noise…
A self-oscillating magnetometer based on the nonlinear magneto-optical rotation effect with separate modulated pump and unmodulated probe beams is demonstrated. This device possesses a bandwidth exceeding $1\khz$. Pump and probe are…
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…
We experimentally demonstrate a simple and robust protocol for the detection of weak radio-frequency magnetic fields using a single electron spin in diamond. Our method relies on spin locking, where the Rabi frequency of the spin is…
Nitrogen vacancy (NV) centers in diamonds have been explored for realizing a wide range of sensing applications in the last decade due to their unique quantum properties. Here we realize a compact and portable magnetometer with an ensemble…
Quantum error correction is of crucial importance for fault-tolerant quantum computers. As an essential step towards the implementation of quantum error-correcting codes, quantum non-demolition (QND) measurements are needed to efficiently…
This work investigates the behavior of a spin-exchange relaxation-free (SERF) magnetometer integrated into the feedback branch of a closed-loop control circuit, designed to actively suppress noise from a current source. In this…
We describe a room-temperature alkali-metal atomic magnetometer for detection of small, high frequency magnetic fields. The magnetometer operates by detecting optical rotation due to the precession of an aligned ground state in the presence…
Classical sensors for spectrum analysis are widely used but lack micro- or nanoscale spatial resolution. On the other hand, quantum sensors, capable of working with nanoscale precision, do not provide precise frequency resolution over a…
In the field of cavity optomechanics, proposals for quantum nondemolition (QND) measurements of phonon number provide a promising avenue by which one can study the quantum nature of nanoscale mechanical resonators. Here, we investigate…
Entanglement can improve the measurement precision of quantum sensors beyond the shot noise limit. Neutral atoms, the basis of some of the most precise and accurate optical clocks and interferometers, do not naturally exhibit all-to-all…
We show how simultaneous, back-action evading tracking of non-commuting observables can be achieved in a widely-used sensing technology, atomic interferometry. Using high-dynamic-range dynamically-decoupled quantum non-demolition (QND)…
Nitrogen vacancy (NV) centers in diamond are atom-scale defects with long spin coherence times that can be used to sense magnetic fields with high sensitivity and spatial resolution. Typically, the magnetic field projection at a single…
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,…
We study the use of squeezed probe light and evasion of measurement back-action to enhance the sensitivity and measurement bandwidth of an optically-pumped magnetometer (OPM) at sensitivity-optimal atom number density. By experimental…
Magneto-optical sensors including spin noise spectroscopies and magneto-optical Kerr effect microscopies are now ubiquitous tools for materials characterization that can provide new understanding of spin dynamics, hyperfine interactions,…