Related papers: Phase-locked amplification enhanced by spin squeez…
Phase shifts induced by the Kerr effect are usually very small at the single-photon level. We propose two circuits for enhancing the cross-Kerr phase shift by applying one- and two-mode quadrature squeezing operators. Our results are based…
Staging laser wake-field acceleration is considered as a necessary technique for developing full-optical jitter-free electron accelerators. Splitting of the acceleration length into several technical parts with their lengths smaller than…
Improving coherence is a fundamental challenge in quantum simulation and sensing experiments with trapped ions. Here we discuss, experimentally demonstrate, and estimate the potential impacts of two different protocols that enhance, through…
We present an experimentally feasible method to produce a large and tunable spin squeezing when an ensemble of many four-level atoms interacts simultaneously with a single-mode photon and classical driving lasers. Our approach is to simply…
Phase-insensitive optical amplifiers uniformly amplify each quadrature of an input field and are of both fundamental and technological importance. We find the quantum limit on the precision of estimating the gain of a quantum-limited…
Spins are prototypical systems with the potential to probe magnetic fields down to the atomic scale limit. Exploiting their quantum nature through appropriate sensing protocols allows to enlarge their applicability to fields not always…
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 derive a phase-entanglement criterion for two bosonic modes which is immune to number fluc- tuations, using the generalized Moore-Penrose inverse to normalize the phase-quadrature operator. We also obtain a phase-squeezing criterion that…
This dissertation studies spin squeezing, entanglement and decoherence in large ensembles of cold, trapped alkali atoms with hyperfine spin f interacting with optical fields. Restricting the state of each atom to a qutrit embedded in the…
Quantum sensing and quantum information processing use quantum advantages such as squeezed states that encode a quantity of interest with higher precision and generate quantum correlations to outperform classical methods. In harmonic…
Pushing the boundaries of measurement precision is central for sensing and metrology, pursued by nonclassical resources such as squeezing, and non-Hermitian degeneracies with distinct spectral response. Their convergence, however, remains…
Propagation of a weak Gaussian probe pulse through a closed loop $\Lambda$ system with permanent dipole moments (PDMs) is investigated in presence of a strong control field along with a third field. The presence of PDMs allows multi photon…
We study the influence of nuclei-induced frequency focusing on the mode locking of spin coherence in quantum dots subjected to a periodic train of optical pulses. In particular, we address the question whether or not nuclei-induced…
Using a quantum theory for an ensemble of three-level atoms (lambda) placed in an optical cavity abd driven by electromagnetic fields, we show that the long-lived spin associated with the ground state sublevels can be squeezed. Two kinds of…
We analyze the creation of spin squeezed atomic ensembles by simultaneous dispersive interactions with several optical frequencies. A judicious choice of optical parameters enables optimization of an interferometric detection scheme that…
We describe a pump-probe scheme with which the spatial asymmetry of dissociating molecular fragments --- as controlled by the carrier-envelope phase of an intense few-cycle laser pulse --- can be enhanced by an order of magnitude or more.…
We present a scheme for achieving amplification of the displacement of the mirror in optomechanical cavity using single-photon postselection where the mirror is initially prepared in squeezed coherent state. The amplification depends on the…
The unconditionally squeezing of the collective spin of an atomic ensemble in a laser driven optical cavity (I. D. Leroux, M. H. Schleier-Smith, and V. Vuletic, Phys. Rev. Lett 104, 073602 (2010)) is studied and analyzed theoretically.…
Multimode squeezed light is a key resource for high-dimensional photonic quantum technologies, enabling applications in quantum-enhanced sensing, quantum communication, and quantum computing. Efficient detection of such a multimode squeezed…
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…