Related papers: Optical two-way time and frequency transfer over f…
Fiber-based remote comparison of $^{87}$Sr lattice clocks in 24 km distant laboratories is demonstrated. The instability of the comparison reaches $5\times10^{-16}$ over an averaging time of 1000 s, which is two orders of magnitude shorter…
We present in this paper results on a new dissemination system of ultra-stable reference signal at 100 MHz on a standard fibre network. The 100 MHz signal is simply transferred by amplitude modulation of an optical carrier. Two different…
Advances in integrated photonics open exciting opportunities for batch-fabricated optical sensors using high quality factor nanophotonic cavities to achieve ultra-high sensitivities and bandwidths. The sensitivity improves with higher…
Optical wave packets that are localized in space and time, but nevertheless overcome diffraction and travel rigidly in free space, are a long sought-after field structure with applications ranging from microscopy and remote sensing, to…
In neutral atom optical clocks, the higher-order atomic polarizability terms lead to the clock transition frequency shift which is motion-state dependent and nonlinear with the optical lattice depth. We propose to use an auxiliary optical…
High-precision optical pulse trains distribution via fibre links has made huge impacts in many fields. In most published works, the accuracies are still fundamentally limited by some unavoidable noises, such as thermal and shot noise from…
Optical communication systems have come through five orders of magnitude improvement in data rate over the last three decades. The increased demand in data traffic and the limited optoelectronic component bandwidths have led to…
The current SI second based on the atomic hyperfine transition in the ground state of 133Cs is expected to be replaced by a new definition based on optical frequency standards, whose estimated uncertainty has now been established two orders…
The transversely confined propagating modes of an optical fiber mediate virtually infinite range energy exchanges among atoms placed within their field, which adds to the inherent free space dipole-dipole coupling. Typically, the single…
Quantum communication technologies capable of operating reliably across heterogeneous optical channels are essential for scalable metropolitan quantum networks. Here we demonstrate high-dimensional time-bin-encoded quantum key distribution…
We present an implementation of the time-frequency (TF) quantum key distribution (QKD) protocol realized mainly with standard telecommunication components at 1550 nm. TF-QKD is implemented with modulations in time and frequency, namely…
Over the last decade of the 20th century and the first few years of the 21st, the uncertainty of atomic clocks has decreased by about two orders of magnitude, passing from the low 10^-14 to below 10^-16, in relative frequency . Space…
The stability of GPS time and frequency transfer is limited by the fact that GPS signals travel through the ionosphere. In high precision geodetic time transfer (i.e. based on precise modeling of code and carrier phase GPS data), the…
Optical lattice clocks (OLCs) enable us to measure time and frequency with a fractional uncertainty at $10^{-18}$ level, which is 2 orders of magnitude better than Cs clocks. In this article, after briefly reviewing OLCs and the history of…
Frequency combs have revolutionized the field of optical spectroscopy, enabling researchers to probe molecular systems with a multitude of accurate and precise optical frequencies. While there have been tremendous strides in direct…
Optical wireless communication (OWC) covering an ultra-wide range of unlicensed spectrum has emerged as an extent efficient solution to mitigate conventional RF spectrum scarcity ranging from communication distances from nm to several…
Free space optical communication has been applied in many scenarios because of its security, low cost and high rates. In such scenarios, a tracking system is necessary to ensure an acceptable signal power. Free space optical links were…
Lossless linear wave propagation is symmetric in time, a principle which can be used to create time reversed waves. Such waves are special 'pre-scattered' spatiotemporal fields, which propagate through a complex medium as if observing a…
We demonstrate fast characterization (~1.4 microseconds) of both the dispersion and dispersion slope of long optical fiber links (~25 km) using dual quadrature spectral interferometry with an optical frequency comb. Compared to previous…
A sharp resonance line that appears in three-photon transitions between the $^{1}S_{0}$ and $^{3}P_{0}$ states of alkaline earth and Yb atoms is proposed as an optical frequency standard. This proposal permits the use of the even isotopes,…