Related papers: Frequency transfer via a two-way optical phase com…
Fiber-delay measurement is one of the key fundamental technologies in numerous fields. Here we propose and experimentally demonstrate a high-precision and concise optical time delay measurement system based on the technique of linear…
In long-haul optical continuous-wave frequency transfer via fiber, remote bidirectional Er$^+$-doped fiber amplifiers are commonly used to mitigate signal attenuation. We demonstrate for the first time the ultrastable transfer of an optical…
The two-way quantum clock synchronization has been shown not only providing femtosecond-level synchronization capability but also security against symmetric delay attacks, thus becoming a prospective method to compare and synchronize…
We use two fiber-based femtosecond frequency combs and a low-noise carrier suppression phase detection system to characterize the optical to microwave synchronization achievable with such frequency divider systems. By applying specific…
We derive relativistic corrections for one-way and two-way time and frequency transfer over optical fibres neglecting no terms that exceed 1 ps in time and $10^{-18}$ in fractional frequency, and estimate their magnitude in typical fibre…
We demonstrate a cascaded optical link for ultrastable frequency dissemination comprised of two compensated links of 150 km and a repeater station. Each link includes 114 km of Internet fiber simultaneously carrying data traffic through a…
To meet the requirements of time-frequency networks and enable frequency downloadability for nodes along the link, we demonstrated the extraction of stable frequency signals at nodes using a mode-locked laser under the condition of 100 km…
We present a fiber-based continuous-variable quantum key distribution system. In the scheme, a quantum signal of two non-orthogonal weak optical coherent states is sent through a fiber-based quantum channel. The receiver simultaneously…
A standard multimode optical fiber can be used as a general purpose spectrometer after calibrating the wavelength dependent speckle patterns produced by interference between the guided modes of the fiber. A transmission matrix was used to…
Fiber-optical networks are a crucial telecommunication infrastructure in society. Wavelength division multiplexing allows for transmitting parallel data streams over the fiber bandwidth, and coherent detection enables the use of…
Quantum mechanics allows the distribution of intrinsically secure encryption keys by optical means. Twin-field quantum key distribution is the most promising technique for its implementation on long-distance fibers, but requires stabilizing…
We demonstrate the generation, 40 km fiber transmission, and homodyne detection of single-mode squeezed states of light at 1550 nm using real-time phase control of a locally generated local oscillator, often called a "real local oscillator"…
We demonstrate a distributed atomic clocks network between Shanghai Institute of Optics and fine Mechanics (SIOM) and Shanghai Institute of Measurement and Test (SIMT). The frequency signals from three different clocks transfer in one fiber…
We demonstrate a new method of light phase shift measurement using a high-finesse optical ring cavity which exhibits reduced phase noise due to cavity length fluctuations. Two laser beams with a frequency difference of one cavity free…
We report the first experimental realization of entanglement swapping over large distances in optical fibers. Two photons separated by more than two km of optical fibers are entangled, although they never directly interacted. We use two…
In this work we present the outcomes of a radio-frequency OAM transmission between two antenna arrays performed in a real-world context. The analysis is supplemented by deep simulative investigations able to provide both a preliminary…
Frequency dissemination in phase-stabilized optical fiber networks for metrological frequency comparisons and precision measurements are promising candidates to overcome the limitations imposed by satellite techniques. However, network…
A polarization switching pulse interleaver is shown to be effective in reducing timing noise due to polarization mode dispersion in time and frequency transfer based on mode-locked lasers and standard single-mode fibres. In closed-loop time…
In long-distance fiber optic transmission, the optic fiber link and erbium-doped fiber amplifiers can introduce excessive noise, which reduces the optical signal-to-noise ratio (OSNR). The narrow-band optical filters can be used to…
Monitoring the optical phase change in a fiber enables a wide range of applications where fast phase variations are induced by acoustic signals or vibrations in general. However, the quality of the estimated fiber response strongly depends…