We study multiparameter sensing of two-dimensional (2D) and three-dimensional (3D) vector fields within the Bayesian framework for SU(2) quantum interferometry. establish a method to determine optimal sensor, which establishes fundamental limit on precision simultaneously estimating multiple parameters with an N-atom sensor. Keeping current experimental platforms in mind, we present sensors that have limited entanglement capabilities yet significantly outperform operate without approach...

We experimentally study electromagnetically induced transparency cooling of the drumhead modes planar two-dimensional arrays with up to N≈190 Be^{+} ions stored in a Penning trap. Substantial sub-Doppler is observed for all N modes. Quantitative measurements center-of-mass mode show near ground-state motional quantum numbers n[over ¯]=0.3±0.2 obtained within 200 μs. The measured rate faster than that predicted by single particle theory, consistent many-body calculation. For lower frequency...

We propose a new type of superradiant laser based on hot atomic beam traversing an optical cavity. show that the theoretical minimum linewidth and maximum power are competitive with best ultracoherent clock lasers. Also, our system operates naturally in continuous wave mode, which has been elusive for lasers so far. Unlike existing lasers, design is simple rugged. This makes it candidate first widely accessible laser, as well to realize sought-after applications challenging environments.

Abstract We propose a protocol for the preparation of generalized Greenberger–Horne–Zeilinger (GHZ) states N atoms each with d = 3 or 4 internal levels. generalize celebrated one-axis twisting (OAT) Hamiltonian qubits to qudits by including OAT interactions equal strengths between every pair qudit levels, we call as balanced (BOAT). Analogous qubits, find that starting from product state an arbitrary number , dynamics under BOAT leads formation GHZ qutrits ( 3) and ququarts 4). While could...

We simulate the dynamics, including laser cooling, of three-dimensional (3-D) ion crystals confined in a Penning trap using newly developed molecular dynamics-like code. The numerical integration ions’ equations motion is accelerated fast multipole method to calculate Coulomb interaction between ions, which allows us efficiently study large with thousands ions. In particular, we show that simulation time scales linearly number, rather than square number. By treating absorption photons as...

The authors propose a readily implementable technique for the efficient cooling of low-frequency planar motion in large two-dimensional ion crystals Penning traps. approach enables rapid to millikelvin temperatures within few milliseconds, paving way sub-Doppler laser and improved quantum information experiments with trapped crystals.

Synchronization has recently been explored deep in the quantum regime with elementary few-level oscillators such as qudits and weakly pumped van der Pol oscillators. To engineer more complex synchronizing systems, it is practically relevant to study composite built from basic units that are commonly available offer high controllability. Here we consider a minimal model for oscillator consisting of two interacting qubits coupled separate baths show this system exhibits wide variety behaviors....

Bragg interferometers, operating using pseudospin-1/2 systems composed of two momentum states, have become a mature technology for precision measurements.State-of-the-art interferometers are rapidly surpassing technical limitations and soon expected to operate near the projection noise limit set by uncorrelated atoms.Despite use large numbers atoms, their operation is governed single-atom physics.Motivated recent proposals demonstrations Raman gravimeters in cavities, we propose scheme...

Using analogies from cavity steady-state superradiance, an experimental scheme for mesoscopic collective spin synchronization is proposed with ion-trap systems, where the in primary species of ions mediated by dissipation a normal vibrational mode induced sympathetic cooling secondary ions.

We show that the onset of steady-state superradiance in a bad cavity laser is preceded by dissipative phase transition between two distinct phases subradiance. The marked non-analytic behavior output power and mean atomic inversion, as well discontinuity variance collective inversion. In particular, for repump rates below critical value, strongly suppressed does not increase with atom number, while it scales linearly number above this value. Remarkably, we find atoms are macroscopic...

We propose a scheme for continuously measuring the evolving quantum phase of collective spin composed $N$ pseudospins. Quantum non-demolition measurements lossy cavity mode interacting with an atomic ensemble are used to directly probe without converting it into population difference. Unlike traditional Ramsey measurement sequences, our allows real-time tracking time-varying signals. As bonus, spin-squeezed states develop naturally, providing estimation significantly more precise than...

Trapped-ion systems are a leading platform for quantum information processing, but they currently limited to 1D and 2D arrays, which imposes restrictions on both their scalability range of applications. Here, we propose path overcome this limitation by demonstrating that Penning traps can be used realize remarkably clean bilayer crystals, wherein hundreds ions self-organize into two well-defined layers. These crystals made possible the inclusion an anharmonic trapping potential, is readily...

Penning traps have been used for performing quantum simulations and sensing with hundreds of ions provide a promising route toward scaling up trapped ion platforms because the ability to trap control or thousands in two- three-dimensional crystals. In both more common radiofrequency Paul traps, lasers are often drive multiqubit entangling operations. A leading source decoherence these operations is off-resonant spontaneous emission. While many computers simulators utilize clock qubits, other...

The creation and manipulation of quantum entanglement is central to improving precision measurements. A principal method generating for use in atom interferometry the process spin squeezing whereupon states become more sensitive $\text{SU}(2)$ rotations. One possibility generate this provided by one-axis twisting (OAT), where a many-particle entangled state one degree freedom generated nonlinear Hamiltonian. We introduce which goes beyond OAT create across two distinct degrees freedom....

Two-dimensional p+ip superconductors and superfluids are systems that feature chiral behavior emerging from the Cooper pairing of electrons or neutral fermionic atoms with nonzero angular momentum. Their realization has been a longstanding goal because they offer great potential utility for quantum computation memory. However, have so far eluded experimental observation both in solid-state as well ultracold gases. Here, we propose to leverage tremendous control offered by rotating...

Penning traps, with their ability to control planar crystals of tens hundreds ions, are versatile quantum simulators. Thermal occupations the motional drumhead modes, transverse plane ion crystal, degrade quality simulations. Laser cooling using electromagnetically induced transparency (EIT cooling) is attractive as an efficient way quickly initialize modes near ground-state occupations. We numerically investigate efficiency EIT in a trap, accounting for complications arising from nature...

Two-dimensional crystals of ions stored in Penning traps are a leading platform for quantum simulation and sensing experiments. For small amplitudes, the out-of-plane motion such can be described by discrete set normal modes called drumhead modes, which used to implement range information protocols. However, experimental observations with Doppler-cooled even near-ground-state-cooled reveal an unresolved mode spectrum. In this work, we establish in-plane thermal fluctuations ion positions as...

We investigate the different photon emission regimes created by a pre-excited and collimated atomic beam passing through single mode of an optical cavity. In regime where cavity degrees freedom can be adiabatically eliminated, we find that atoms undergo superradiant when collective linewidth exceeds transit-time broadening. analyze case direction is slanted with respect to axis. For this situation, phase continuous light similar steady-state superradiance established providing tilt...

We examine the dynamics of subsystems bipartite and tripartite quantum systems with nonlinear Hamiltonians.We consider two models which capture generic features open systems: a three-level atom interacting single-mode radiation field, field modes do not directly interact each other.The entanglement specific initially unentangled states atom-field system is examined through time-varying subsystem von Neumann entropy (SVNE).The counterparts near-revivals fractional revivals initial state are...

Planar thermal equilibration is studied using direct numerical simulations of ultracold two-dimensional (2D) ion crystals in a Penning trap with rotating wall. The large magnetic field the splits modes that describe in-plane motion ions into two branches: High frequency cyclotron dominated by kinetic energy and low $\mathbf{E \times B}$ potential associated position displacements. Using an eigenmode analysis we extract rate between these branches as function ratio frequencies characterize...

We study optimal quantum sensing of multiple physical parameters using repeated measurements. In this scenario, the Fisher information framework sets fundamental limits on performance, yet states and corresponding measurements that attain these remain to be discovered. To address this, we extend approach with a second optimality requirement for sensor provide unambiguous estimation unknown parameters. propose systematic method integrating Bayesian approaches metrology identify combination...

We study the phenomenon of quantum synchronization from viewpoint metrology. By interpreting self-sustained oscillators as dissipative sensors, we develop a framework to characterize several aspects synchronization. show that Fisher information (QFI) serves system-agnostic measure also carries clear operational meaning, viz., it quantifies precision with which amplitude weak synchronizing drive can be measured. extend our analysis many-body subjected multiple drives. how QFI matrix used...

We simulate the dynamics, including laser cooling, of 3D ion crystals confined in a Penning trap using newly developed molecular dynamics-like code. The numerical integration ions' equations motion is accelerated fast multipole method to calculate Coulomb interaction between ions, which allows us efficiently study large with thousands ions. In particular, we show that simulation time scales linearly number, rather than square number. By treating absorption photons as Poisson process,...