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An all-optical computer has remained an elusive concept. To construct a practical computing primitive equivalent to an electronic Boolean logic, one should utilize nonlinearity that overcomes weaknesses that plague many optical processing schemes. An advantageous nonlinearity provides a complete set of logic operations and allows cascaded operations without changes in wavelength or in signal encoding format. Here we demonstrate an all-optical majority gate based on a vertical-cavity surface-emitting laser (VCSEL). Using emulated signal coupling, the arrangement provides Bit Error Ratio (BER) of 10−6 at the rate of 1 GHz without changes in the wavelength or in the signal encoding format. Cascaded operation of the injection-locked laser majority gate is simulated on a full adder and a 3-bit ripple-carry adder circuits. Finally, utilizing the spin-flip model semiconductor laser rate equations, we prove that injection-locked lasers may perform normalization operations in the steady-state with an arbitrary linear state of polarization.

We present an all-optical computing scheme based on normalization operations of injection-locked lasers. We show cascaded operations in cellular automaton by an all-optical Conway’s Game of Life and simulate 100 generations of gaming.

We experimentally demonstrate BER reduction and orthogonal modulation using an injection locked single-mode VCSEL. It allows us suppressing an amplitude noise of optical signal and/or double the capacity of an information channel.

We present a new method for quantification of minute birefringence in high-finesse resonators. The method is based on observing the homodyne polarization mode beat at the output of the resonator. We show that the mode beat is generated by a phase mismatch of a polarization mode in the cavity and that the magnitude of the birefringence is proportional to the beat frequency. We demonstrate the sensitivity of the technique by measuring polarization properties of a twisted 0.275 m long single-mode fiber cavity. Maximum beat length of the fiber was found to be 10.6 m, which is almost 40 times longer than the length of the studied fiber.

In this paper, we propose and experimentally demonstrate a pressure sensor based on birefringent single mode fiber FP cavity using optical heterodyne. The proof of concept device consists of a light source, a polarizer controller, a modulator, a RF generator, a single mode fiber Fabry-Perot cavity, a strain inspector, an erbium doped fiber amplifier, a filter, a polarizer, an optical spectrum analyzer, and a digital communication analyzer. The dynamic range of the proposed sensor is explored. The results demonstrate the new concept of fiber pressure sensors and the technical feasibility for pressure measurements.

Future transparent networks require optical regeneration. The regeneration process of amplitude-modulated signals consists of three key stages: re-amplification, re-shaping, and re-timing. In this Paper we briefly review various optical clock recovery methods and propose a polarization insensitive low-cost scheme capable of resolving timing information simultaneously for multiple wavelength channels. We also discuss the prospects of low-cost volume production with integrated optics and especially with Si-photonics.

We introduce a polarization insensitive scheme for all-optical clock recovery and demonstrate how it works with data signals highly distorted by chromatic dispersion and self-phase modulation. The scheme which is known for its multi-wavelength and multi-data-rate capabilities is based on a birefringent fiber resonator and a polarizer. In this article we show how it can handle data signals which have undergone distortion due to transmission over dispersive and nonlinear fiber-optic propagation paths and which come in with arbitrary polarization orientation. Bit-pattern dependent amplitude fluctuations of the recovered clock signal are equalized by means of a semiconductor optical amplifier operated in saturation. The experimental results which, as a proof-of-concept, are obtained from single-wavelength channel 10 Gbit/s return-to-zero data agree well with numerical simulations.

A novel measurement principle for fiber-optic sensing is presented. Use of a cavity-ring-down scheme enables measurements of minute optical losses in high-finesse fiber-optic cavities. The loss may be induced by evanescent-field absorption, fiber bending, fiber degradation, Bragg gratings, or any other effect that might change the fiber transmission or cavity reflector properties. The principle is proved to be rather insensitive to ambient perturbations such as temperature changes. A high-sensitivity measurement of loss due to bending is presented as a proof-of-principle. With a cavity finesse of 627 a sensitivity for induced loss of 108 ppm (4.68 x 10(-4) dB) is achieved. Preliminary measurements of evanescent-field absorption are also discussed.

A polarization independent multiwavelength all-optical clock recovery scheme based on a birefringent resonator is introduced. We verify proper operation of the method with data signals highly distorted by dispersion and fiber nonlinearity.