Massachusetts Institute of Technology

Other

Hosain Hakimi

Farhad Hakimi

Kristin A Rauschenbach

Daniel T Moriarty

A process shifts wavelengths of optical pulses. The process includes transmitting an incoming optical pulse through a nonlinear optical material, splitting the transmitted pulse into a plurality of mutually coherent optical pulses, and recombining the mutually coherent pulses with temporal delays. The recombined pulses produce a temporal interference pattern. The pattern has a peak whose wavelength is shifted with respect to the wavelength of the incoming optical pulse.

Fast optical wavelength shifter

A method introduces variable time offsets into a stream of optical pulses. The method includes receiving a plurality of coherent optical pulses, receiving a plurality of control signals, and forming a coherent pulse array (CPA) from each pulse in response to one of the received control signals. Temporal spacings between pulses of each CPA are responsive to the associated one of the received control signals. For optical control signals, response times can be very short. The method further includes transmitting each pulse through a dispersive optical medium. The act of transmitting makes pulses of each CPA overlap to form an interference pattern.

Fast variable optical delay

A method produces a wavelength shift into an optical signal. The method includes producing a coherent temporal array of optical signals (CTAS) from an incoming optical signal and broadening the signals of the CTAS to produce a interference pattern. The broadening results from transmitting the CTAS or the incoming optical signal through a dispersive medium. The method also includes selectively transmitting a peak of the interference pattern. The transmitted peak has a selected wavelength shift with respect to the incoming optical signal.

Wavelength shifting and optical switching

A method of transmitting optical pulses in a transmission media includes separating a coherent source optical pulse into a plurality of mutually coherent pulses, and producing a series of mutually coherent optical pulses from the plurality of pulses. The series is transmitted through the media, and the pulses of the series are received at a distant region of the media. The series of pulses is adapted to interfere and form a packet whose width is narrower than the width of any pulse of the series at the distant region.

Quasi-dispersionless optical fiber transmission, dispersion compensation and optical clock

A method of generating a signal including: generating a first sequence of coherent optical pulses which are sufficiently close in spacing so as to overlap and interfere upon traveling a predetermined length down an optical fiber to form a first interference pattern with a first central lobe having a characteristic wavelength, wherein the energy of the pulses of the first sequence of pulses is within the non-linear regime of the optical fiber; manipulating the first sequence of optical pulses; in a similar manner generating a second sequence of coherent optical pulses; manipulating the second sequence of optical pulses; and introducing both the first and second manipulated sequences of pulses into the optical fiber, wherein the manipulating of the pulses of the first and the second sequence of pulses shifts the characteristic wavelengths of the first and second central lobes, respectively, to first and second transmission signal wavelengths.

WDM system that uses nonlinear temporal gratings

A method of generating a signal pulse in an optical fiber characterized by dispersion and a refraction index that has a nonlinear regime of operation, the method including generating a sequence of coherent optical pulses each of which has an associated energy; and introducing the sequence of pulses into the optical fiber, wherein the pulses in the sequence of pulses are sufficiently close in spacing so that after traveling a predetermined length down the optical fiber, the pulses of the sequence of pulses overlap and interfere to form an interference pattern, and wherein the associated energy of at least one of the pulses of the sequence of pulses is within the nonlinear regime of the optical fiber.

Nonlinear temporal grating as a new optical solitary wave

An optical amplifier includes first and second optical fibers. The first optical fiber has a core, a first cladding surrounding the core and a second cladding surrounding the first cladding. The second optical fiber has an end physically coupled to a side portion of the first optical fiber. The end transmits light to the first cladding.

Side pumped optical amplifiers and lasers

Chromatic and polarization dispersion and transmitter frequency chirp are the dominant data rate limiting factors for high-speed, long distance communication systems. To overcome such limitations, a chromatic and polarization dispersion and frequency chirp compensator is utilized. The applicants provide a compensator by combining a wavelength to polarization transformer with a polarization to delay converter having a dispersion characteristic of substantially equivalent in magnitude, and opposite in sign, to the desired amount of dispersion and frequency chirp to be compensated. Optical gain may be incorporated in any of the elements of the compensator which makes the present invention a lightwave amplifier as well as a dispersion compensator. The present invention is also applicable as an optical pulse time compressor that compresses a relatively long width optical pulse to a short width pulse.

Apparatus for compensating chromatic and polarization dispersion and

A system for aligning an optical fiber termination to a light path is disclosed. Light coming through the fiber at its termination as well as light introduced into the light path from a laser are directed along the light path to a viewer. The placement of the fiber termination is adjustable, as is the direction of the light path, such that the image of light from the optical fiber termination can be adjusted to coincide at the viewer with the image of light from the laser. A long focal length lens is optionally placed in the input beam path and laterally positioned as a fine resolution control over the point of focus at the fiber core. If the laser radiation is ultraviolet or infrared, a flourescing surface may be positioned in the light path to return visible light along the light path to the viewer.

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Watertown, MA, United States of America

Hosain Hakimi