Romain Bonjour

Direct Conversion of Free Space Millimeter Waves to Optical Domain by Plasmonic Modulator Antenna

A scheme for the direct conversion of millimeter and THz waves to optical signals is introduced. The compact device consists of a plasmonic phase modulator that is seamlessly cointegrated with an antenna. Neither high-speed electronics nor electronic amplification is required to drive the modulator. A built-in enhancement of the electric field by a factor of 35 000 enables the direct conversion of millimeter-wave signals to the optical domain. This high enhancement is obtained via a resonant antenna that is directly coupled to an optical field by means of a plasmonic modulator. The suggested concept provides a simple and cost-efficient alternative solution to conventional schemes where millimeter-wave signals are first converted to the electrical domain before being up-converted to the optical domain.

Reflective-SOA Fiber Cavity Laser as Directly Modulated WDM-PON Colorless Transmitter

Reflective semiconductor optical amplifier (RSOA) fiber cavity lasers are attractive colorless, self-seeded, self-tuning, and directly modulatable sources for passive optical networks (PONs). They comprise of an RSOA in the optical network unit as the active element, a distribution fiber as the laser cavity, a waveguide grating router, and a common reflective mirror with the latter two positioned at the remote node. In this paper, we introduce a model and perform simulations to elucidate the recently discovered successful operation of this new PON source. The results are in agreement with experiments; the formation of a narrow laser spectrum with a relatively constant output power is seen despite a relatively broad passband window of the waveguide grating router. We further study mode competition and mode partition noise. It is shown that proper chromatic dispersion management can overcome mode partition noise limitations. The quality of the RSOA fiber cavity laser does not degrade when being directly modulated and as a result these highly multimode lasers offer an economic way to transport Gbit/s upstream data over kilometers of fiber in a wavelength division multiplexing-PON.

Continuously tunable true-time delays with ultra-low settling time

Ultra-fast, continuously tunable true-time delays are key components in many microwave and optical communications subsystems. In this paper, we introduce and demonstrate a new implementation method of a continuously tunable true-time delay featuring a settling time in the order of tens of picoseconds. Our solution relies on the splitting and combining of complementary phased shifted spectra (CPSS). It works for large bandwidth signals, has a low complexity, offers moderate losses, and can be fully integrated.

High speed plasmonic modulator array enabling dense optical interconnect solutions

Plasmonic modulators might pave the way for a new generation of compact low-power high-speed optoelectronic devices. We introduce an extremely compact transmitter based on plasmonic Mach-Zehnder modulators offering a capacity of 4 × 36 Gbit/s on a footprint that is only limited by the size of the high-speed contact pads. The transmitter array is contacted through a multicore fiber with a channel spacing of 50 μm.

Plasmonic Organic Hybrid Modulators—Scaling Highest Speed Photonics to the Microscale

Complementing plasmonic slot waveguides with highly nonlinear organic materials has rendered a new generation of ultracompact active nanophotonic components that are redefining the state of the art. In this paper, we review the fundamentals of this so-called plasmonic- organic-hybrid (POH) platform. Starting from simple phase shifters to the most compact IQ modulators, we introduce key devices of high-speed data communications. For instance, all-plasmonic Mach-Zehnder modulators (MZMs) are reviewed and long-term prospects are discussed. This kind of modulator already features unique properties such as a small footprint (<; 20 μm2), a large electro-optic bandwidth (> 110 GHz), a small energy consumption (~25 fJ/b), a large extinction ratio (> 25 dB) in combination with a record small voltage-length product of 40 Vμm. Finally, as an example for seamless integration we introduce novel plasmonic IQ modulators. With such modulators we show the generation of advanced modulation formats (QPSK, 16-QAM) on footprints as small as 10 μm × 75 μm. This demonstration ultimately shows how plasmonics can be used to control both phase and amplitude of an optical carrier on the microscale with reasonably low losses.

Ultra-fast tunable true-time delay using complementary phase-shifted spectra (CPSS)

We introduce an ultra-fast, continuously tunable true-time delay, featuring settling times of tens of picoseconds. Our solution operates for large bandwidth signals, has a low complexity, low losses, and can be fully integrated.

Ultra-Fast Millimeter Wave Beam Steering

In this paper, we demonstrate ultra-fast millimeter wave beam steering with settling times below 50 ps. A phased array antenna with two elements is employed to realize beam steering. The phased array feeder is implemented with a recently introduced time delay line that provides, at the same time, an ultra-fast tunability, broadband operation, and continuous tuning. Our implementation is used to perform symbol-by-symbol steering. In our demonstration, the beam direction is switched between two sequentially transmitted symbols toward two receivers placed 30° apart. We show the successful symbol-by-symbol steering for data streams as fast as 10 GBd. The suggested scheme shows that the ultra-fast beam steering is becoming practical and might ultimately enable novel high bit-rate multiple access schemes.

Ultra-compact plasmonic IQ-modulator

Plasmonic IQ-modulators with a record small footprint are demonstrated to operate up to 72 GBd. The devices have shown the ability to encode QPSK and 16-QAM modulation formats with power consumption as low as 27 fJ/bit at 18 GBd-16QAM.

Pre-equalization technique enabling 70 Gbit/s photonic-wireless link at 60 GHz

We demonstrate a 70 Gbit/s photonic wireless link on a single carrier at 60 GHz using a single polarization. To our knowledge, this is the highest data rate on a single polarization 60 GHz carrier.

Plasmonic phased array feeder enabling symbol-by-symbol mm-wave beam steering at 60 GHz

We demonstrate an on-chip 60 GHz phased array antenna feeder with record-low footprint (active area <;2.5μm2), based on ultra-compact plasmonic modulators. The chip footprint is only limited by the contact pads size. Our implementation also enables ultra-fast steering with less than 1 ns reconfiguration time.