Magnetometry, that is, the measurement of magnetic fields, has applications range from brain imaging to exploration outer Solar System. The best magnetometry technologies achieve a sensitivity close Planck's constant, number appears in Heisenberg uncertainty relation. This Colloquium reviews what is known about quantum mechanical limits on field sensing, and identifies new sensing approaches may break current impasse sensitivity.

We demonstrate a double optical frequency reference (1529 and 1560 nm) for the telecom C-band using 87Rb modulation transfer spectroscopy. The two frequencies are defined by 5S(1/2)F=2→5P(3/2)F'=3 two-level 5S(1/2)F=2→5P(3/2)F'=3→4D(5/2)F''=4 ladder transitions. examine sensitivity of stabilization to probe power magnetic field fluctuations, calculate its shift due residual amplitude modulation, estimate gas collisions. short-term Allan deviation was estimated from error signal slope Our...

We present a magnetic sensor with energy resolution per bandwidth [Formula: see text] show how

We describe a compact, robust and versatile system for studying magnetic dynamics in spinor Bose-Einstein condensate. Condensates of 87 Rb are produced by all-optical evaporation 1560 nm optical dipole trap, using non-standard loading sequence that employs an auxiliary 1529 beam partial compensation the strong differential light shift induced trap itself. use near-resonance Faraday rotation probing to non-destructively track condensate magnetization, demonstrate few-Larmor-cycle tracking...

We describe a comagnetometer employing the f=1 and f=2 ground state hyperfine manifolds of ^{87}Rb spinor Bose-Einstein condensate as colocated magnetometers. The feature nearly opposite gyromagnetic ratios thus sum their precession angles is only weakly coupled to external magnetic fields, while being highly sensitive any effect that rotates both in same way. transverse magnetizations azimuth are independently measured by nondestructive Faraday rotation probing, we demonstrate 44.0(8) dB...

Optical trapping of atoms employs high-intensity fields that necessarily alter atomic level structure. The calculation light shifts by perturbation theory fails for scenarios arise, example, when the is near an excited-state transition or polychromatic fields. We show here non-perturbative methods based on Floquet’s theorem elegantly handle such scenarios. compare our to precision absorption spectroscopy cold 87Rb in a bichromatic optical dipole trap at 1560 + 1529 nm. Proximity resonances...

Entangled photons are generally collected by detection systems that select their certain spatial modes, for example using single-mode optical fibers. We derive simple and easy-to-use expressions allow us to maximize the coupling efficiency of entangled with specific orbital angular momentum (OAM) correlations generated means spontaneous parametric downconversion. Two different configurations considered: one in which beams OAM conversion from without OAM, second when directly nonlinear...

We present interferometeric measurements of the $f=1$ to $f=2$ interhyperfine scattering lengths in a single-domain spinor Bose-Einstein condensate $^{87}\mathrm{Rb}$. The interaction leads strong and state-dependent modification spin-mixing dynamics with respect noninteracting description. employ hyperfine-specific Faraday-rotation probing reveal evolution transverse magnetization each hyperfine manifold for different state preparations, comagnetometer strategy cancel laboratory magnetic...

We consider the interaction of a ferromagnetic spinor Bose-Einstein condensate with magnetic field gradient. The gradient realizes spin-position coupling that explicitly breaks time-reversal symmetry T and space parity P, but preserves combined PT symmetry. observe using numerical simulations, first-order phase transition spontaneously breaking this re-maining to low-gradient phase, in which effects are frozen out by interaction, suggests possibility high-coherence sensors unaffected dephasing.

We report on an experiment for generating singlet states in a cold atomic ensemble. use quantum non-demolition measurement and feedback control to produce macroscopic spin state with total zero reduced fluctuations.

We present a non-perturbative numerical technique for calculating strong light shifts in atoms under the influence of multiple optical fields with arbitrary polarization. confirm our experimentally by performing spectroscopy cloud cold $^{87}$Rb subjected to $\sim$ kW/cm$^2$ intensities at 1560.492 nm simultaneous 1529.269 or 1529.282 nm. In these conditions excited state resonances 1529.26 and 1529.36 induce level mixing are highly nonlinear. By absorption spectroscopy, we observe that...

We demonstrate a double optical frequency reference (1529 nm and 1560 nm) for the telecom C-band using $^{87}$Rb modulation transfer spectroscopy. The two frequencies are defined by 5S$_{1/2} F=2 \rightarrow $ 5P$_{3/2} F'=3$ two-level F'=3 4D$_{5/2} F"=4$ ladder transitions. examine sensitivity of stabilization to probe power magnetic field fluctuations, calculate its shift due residual amplitude modulation, estimate gas collisions. short-term Allan deviation was estimated from error signal...

Many studies on microscopic systems deal with Brownian particles embedded in media whose densities are different from that of the particles, causing them either to sink or float. The proximity a wall modifies friction force particle experiences, being, instead Stokes assumed by Einstein and Langevin, function separation distance, as described Faxen. In this work we present thorough analysis bidimensional motion using monodisperse suspensions latex beads controlled temperatures. By means...

Summary form only given. We propose a new method to produce continuous source of spin-polarized cold atoms which are all-optically guided after their extraction from magneto-optical trap (MOT), as depicted in Fig. 1 (a). The techniques combines several physical effects and relies on light-shift engineering [Fig. (b)], implemented using two coaxially overlapped optical beams each one driving given transition three-level atom ladder configuration (Ξ-system). In well chosen configuration, the...