arXiv subjects

Marco Pomponio

Publications and source records attributed to Marco Pomponio.

4 recordsLinked to original sources

arXiv2026

Redefining the limits of real-time noise cancellation in optical fiber links

A broad and growing array of applications rely on the faithful transmission of ultrastable optical signals over noisy paths, requiring cancellation of environmentally induced noise. A generally accepted limit constrains how well the path length noise can be suppressed in real time. Here, we show that this standard limit is not fundamental and can be improved upon. By considering the temporal correlations between the round-trip and one-way signals, we develop a new framework for optimizing the noise cancellation feedback signal for any spatial distribution of noise along the signal path. We use this framework to surpass the standard limit in two sets of experiments. First, we demonstrate noise cancellation in a deployed urban optical fiber, where we achieve noise suppression approximately 6 dB beyond the standard limit. Then, in a reconfigurable lab-based fiber-optic testbed, we show that, for certain spatial distributions of noise, suppression of well over 10 dB beyond the standard limit is readily achievable. With the use of digital signal processing to generate the correction signal, our new technique requires no new electro-optic hardware relative to the field-standard noise cancellation scheme. This will allow for widespread adoption of these improved limits in existing systems, with applications in optical clock distribution, optical clock comparisons for fundamental physics and geodesy, and quantum networking.

physics.optics↗

arXiv2024

Deployment of a Transportable Yb Optical Lattice Clock

We report on the first deployment of a ytterbium (Yb) transportable optical lattice clock (TOLC), commercially shipping the clock 3,000 km from Boulder, Colorado to Washington DC. The system, composed of a rigidly mounted optical reference cavity, atomic physics package, and an optical frequency comb, fully realizes an independent frequency standard for comparisons in the optical and microwave domains. The shipped Yb TOLC was fully operational within 2 days of arrival, enabling frequency comparisons with rubidium (Rb) fountains at the United States Naval Observatory (USNO). To the best of our knowledge, this represents the first deployment of a fully independent TOLC, including the frequency comb, coherently uniting the optical stability of the Yb TOLC to the microwave output of the Rb fountain.

physics.atom-ph↗

arXiv2021

10 GHz Generation with Ultra-Low Phase Noise via the Transfer Oscillator Technique

Coherent frequency division of high-stability optical sources permits the extraction of microwave signals with ultra-low phase noise, enabling their application to systems with stringent timing precision. To date, the highest performance systems have required tight phase stabilization of laboratory grade optical frequency combs to Fabry-Perot optical reference cavities for faithful optical-to-microwave frequency division. This requirement limits the technology to highly-controlled laboratory environments. Here, we employ a transfer oscillator technique, which employs digital and RF analog electronics to coherently suppress additive optical frequency comb noise. This relaxes the stabilization requirements and allows for the extraction of multiple independent microwave outputs from a single comb, while at the same time, permitting low-noise microwave generation from combs with higher noise profiles. Using this method we transferred the phase stability of two high-Finesse optical sources at 1157 nm and 1070 nm to two independent 10 GHz signals using a single frequency comb. We demonstrated absolute phase noise below -106 dBc/Hz at 1-Hz from carrier with corresponding 1 second fractional frequency instability below $2\times10^{-15}$. Finally, the latter phase noise levels were attainable for comb linewidths broadened up to 2 MHz, demonstrating the potential for out-of lab use with low SWaP lasers.

physics.optics↗

arXiv2019

A scalable hardware and software control apparatus for experiments with hybrid quantum systems

Modern experiments with fundamental quantum systems - like ultracold atoms, trapped ions, single photons - are managed by a control system formed by a number of input/output electronic channels governed by a computer. In hybrid quantum systems, where two or more quantum systems are combined and made to interact, establishing an efficient control system is particularly challenging due to the higher complexity, especially when each single quantum system is characterized by a different timescale. Here we present a new control apparatus specifically designed to efficiently manage hybrid quantum systems. The apparatus is formed by a network of fast communicating Field Programmable Gate Arrays (FPGAs), the action of which is administrated by a software. Both hardware and software share the same tree-like structure, which ensures a full scalability of the control apparatus. In the hardware, a master board acts on a number of slave boards, each of which is equipped with an FPGA that locally drives analog and digital input/output channels and radiofrequency (RF) outputs up to 400 MHz. The software is designed to be a general platform for managing both commercial and home-made instruments in a user-friendly and intuitive Graphical User Interface (GUI). The architecture ensures that complex control protocols can be carried out, such as performing of concurrent commands loops by acting on different channels, the generation of multi-variable error functions and the implementation of self-optimization procedures. Although designed for managing experiments with hybrid quantum systems, in particular with atom-ion mixtures, this control apparatus can in principle be used in any experiment in atomic, molecular, and optical physics.

physics.ins-det↗