Related papers: Frequency Stability of Atomic Frequency Standards …
The low frequency region of the spectrum is a challenging regime for quantum probes. We support the idea that, in this regime, performing Ramsey measurements carefully controlling the time at which each measurement is initiated is an…
We address a phase estimation scheme using Gaussian states in the presence of non-Gaussian phase noise. At variance with previous analysis, we analyze situations in which the noise occurs before encoding phase information. In particular, we…
The detection of gravitational waves has ushered in a new era of observing the universe. Quantum resource advantages offer significant enhancements to the sensitivity of gravitational wave observatories. While squeezed states for…
Quantum repeaters are required for long-distance quantum communication. For efficient coupling of quantum entangled photon sources with narrow-linewidth quantum memories we performed the frequency stabilization of two lasers at 1514 and…
For the optical generation of ultrastable microwave signals for fountain clocks we developed a setup, which is based on a cavity stabilized laser and a commercial frequency comb. The robust system, in operation since 2020, is locked to a…
We propose a novel approach to all-optical frequency standard design, based on a counterintuitive combination of the coherent population trapping effect and signal discrimination at the maximum of absorption for the probe radiation. The…
Interactions between atoms and lasers provide the potential for unprecedented control of quantum states. Fulfilling this potential requires detailed knowledge of frequency noise in optical oscillators with state-of-the-art stability. We…
The resonance fluorescence from regular atomic systems is shown to represent a continuous source of non-Gaussian entangled radiation propagating in two different directions. For a single atom entanglement occurs under the same conditions as…
Optical frequency combs are utilized in a wide range of optical applications, including atomic clocks, interferometers, and various sensing technologies. They are often generated via four-wave mixing in chip-integrated microring resonators,…
Quantum entanglement can provide enhanced precision beyond standard quantum limit (SQL), the highest precision achievable with classical means. It remains challenging, however, to observe large enhancement limited by the experimental…
The squeezing spectrum of the fluorescence field emitted from a four-level atom in $J=1/2$ to $J=1/2$ configuration driven by two coherent fields is studied. We find that the squeezing properties of the fluorescence radiation are…
The dynamics of quantum systems are unavoidably influenced by their environment and in turn observing a quantum system (probe) can allow one to measure its environment: Measurements and controlled manipulation of the probe such as dynamical…
One of the noise sources that currently limits gravitational wave (GW) detectors comes from the quantum nature of the light causing uncertain amplitude and phase. Phase uncertainty limits the precision of an interferometric measurement.…
Exquisite sensitivities are a prominent advantage of quantum sensors. Ramsey sequences allow precise measurement of direct current fields, while Hahn-echo-like sequences measure alternating current fields. However, the latter are restrained…
At absolute zero temperature, thermal noise vanishes when a physical system is in its ground state, but quantum noise remains as a fundamental limit to the accuracy of experimental measurements. Such a limitation, however, can be mitigated…
We theoretically propose an efficient way to generate and detect squeezed light by a single qubit in circuit QED. By tuning the qubit energy splitting close to the fundamental frequency of the first harmonic mode (FHM) in a transmission…
We study the estimation precision attainable by entanglement-enhanced Ramsey interferometry in the presence of spatiotemporally correlated non-classical noise. Our analysis relies on an exact expression of the reduced density matrix of the…
A thermal atomic ensemble-based laser source with superior frequency stability is proposed that relies on the accumulated contributions from an abundance of nonzero-transverse-velocity atomic ensembles. Compared with the traditional case in…
Quantum sensors promise revolutionary advances in medical imaging, energy production, mass detection, geodesy, foundational physics research, and a host of other fields. In many sensors, the signal takes the form of a changing qubit…
Quantum measurements of mechanical systems can produce optical squeezing via ponderomotive forces. Its observation requires high environmental isolation and efficient detection, typically achieved by using optical cavities and cryogenic…