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We demonstrate an electro-optic sampling technique for high-resolution acquisition of few-photon signals. The temporal features of a biphoton distribution are observed with 98 ps resolution using slow detectors with a response extending >1 ns.

We demonstrate high-speed detection of low-photon waveforms using slow off-the-shelf detectors. Using a detector with a distorted instrument response function spanning > 1 ns, we recover single photon waveforms at a resolution of 60 ps.

We introduce a novel method to controllably improve the performance of photonic quantum random number generators by using minimum information entropy per bit as a standalone design parameter.

We experimentally demonstrate intensity amplification of repetitive picosecond optical pulses with an input-to-output gain up to 5.5 dB using a passive Talbot amplifier. Through the dispersion-induced temporal Talbot effect, the amplifier uses electro-optic phase modulation and a low-loss dispersive medium to exploit and coherently redistribute the energy of the original pulse train into fewer, replica, amplified pulses. In addition, we show how our passive amplifier mitigates the pulse train timing-jitter and pulse-to-pulse intensity fluctuations above a specific cutoff frequency., 4 pages, 5 figures

The temporal Talbot effect comprises a set of self-imaging phenomena in which a pulse train undergoes various coherence revivals after propagation through a dispersive medium. Besides the intrinsic physical interest of the phenomenon itself, the effect has found practical applications in various scientific areas. In optical signal processing, the temporal Talbot effect has been used to multiply the repetition-rate of periodic pulse sequences by integer factors. Because it operates coherently on the frequencies that comprise a pulse train, the temporal Talbot effect has been shown to mitigate noise such as reduction of pulse-to-pulse timing jitter and amplitude variation, as well as real-time optical averaging. Recently, there has been renewed interest in the temporal Talbot effect due to its use in arbitrary repetition rate multiplication and division, not just integer multiplication. Arbitrary repetition-rate control is based on a suitable combination of temporal phase-modulation and spectral-phase filtering using temporal Talbot conditions. By adjusting the phase-modulation profile and group-velocity dispersion, the multiplication and division factors can be tuned to be any desired values- fractional or integer. One of the main advantages of this methodology compared to traditional approaches of repetition rate control is its energy efficiency. Because temporal and spectral phase filtering are lossless processes, pulse trains using Talbot-based repetition rate control only suffer insertion loss from the system. In this article, we first present an overview of the theory behind temporal Talbot effects and then review recent work on its application for realizing arbitrary control of the repetition-rate of periodic optical pulses. This platform enables the creation of simple, versatile optical pulse sources for diverse applications where customized repetition rates are necessary.

We introduce and experimentally demonstrate a new design for passive Talbot amplification of repetitive optical waveforms, in which the gain factor can be electrically reconfigurable. The amplifier setup is composed of an electro-optic phase modulator followed by an optical dispersive medium. In contrast to conventional Talbot amplification, here we achieve different amplification factors by using combinations of fixed dispersion and programmable temporal phase modulation. To validate the new design, we experimentally show tunable, passive amplification of picosecond optical pulses with gain factors from m = 2 to 30 using a fixed dispersive line (a linearly chirped fiber Bragg grating).

We propose and experimentally demonstrate the first design of a fiber-optics programmable base/sub-harmonic optical clock recovery circuit, involving a phase modulator and linear dispersion, in which the rate division factor can be electrically reconfigurable through the modulation driving waveform.

We introduce a new design for Talbot-based passive amplifiers, involving temporal phase modulation and dispersion, in which the gain factor can be electrically reconfigurable. In particular, we show gain factors from m = 2 to 30 using a fixed dispersive line (FBG).

We experimentally demonstrate input-to-output gain in a Talbot amplifier, operating without using any active gain process, by recycling energy already stored in the input repetitive signal. We show a gain factor exceeding the total system loss by 5dB.

We propose and experimentally demonstrate repetition-rate multiplication of picosecond optical pulse trains by a fractional factor based on temporal self-imaging, involving temporal phase modulation and first-order dispersion. Multiplication factors of 1.25, 1.33, 1.5, 1.6, 1.75, 2.25, 2.33, and 2.5 are achieved with high fidelity from a mode-locked laser with an input repetition-rate between 10 and 20 GHz.