Abstract: A laser device is provided for generating a helical-shaped optical wave and includes: (i) a gain region located between one first end defined by a first mirror and a second end defined by an exit region, (ii) a second mirror arranged so as to form with the first mirror an optical cavity including the gain region and a gap between the exit region and the second mirror, (iii) apparatus for pumping the gain region so as to generate the optical wave, wherein the laser device further includes at least one apparatus for shaping the light intensity and/or phase profiles of the optical wave and arranged for selecting at least one rotary-symmetrical transverse mode of the optical wave, the rotary-symmetrical transverse mode being chosen between those with a radial index equal to zero and with an azimuthal index being an integer with a module higher or equal to 1.

Abstract: A laser device for generating an optical wave including at least two frequencies, such laser device including: a first element including a gain region, a second mirror, distinct from the first element, and arranged so as to form with a first mirror an optical cavity including the gain region; means for pumping the gain region so as to generate the optical wave; means for shaping the light intensity of the optical wave arranged for selecting at least two transverse modes of the optical wave; and means for shaping the longitudinal and/or transversal phase profile of the optical wave and arranged for adjusting at least two transverse modes of the optical wave.

Abstract: A laser device is provided for generating a helical-shaped optical wave and includes: (i) a gain region located between one first end defined by a first mirror and a second end defined by an exit region, (ii) a second mirror arranged so as to form with the first mirror an optical cavity including the gain region and a gap between the exit region and the second mirror, (iii) apparatus for pumping the gain region so as to generate the optical wave, wherein the laser device further includes at least one apparatus for shaping the light intensity and/or phase profiles of the optical wave and arranged for selecting at least one rotary-symmetrical transverse mode of the optical wave, the rotary-symmetrical transverse mode being chosen between those with a radial index equal to zero and with an azimuthal index being an integer with a module higher or equal to 1.

Abstract: A laser device is provided for generating an optical wave at a laser frequency, including (i) a semiconductor element having a gain region with quantum wells, the gain region being located between a first mirror and an exit region defining an optical microcavity, (ii) a second mirror distinct from the semiconductor element and arranged so as to form with the first mirror an external optical cavity including the gain region, (iii) a pump for pumping the gain region so as to generate the optical wave, wherein the optical microcavity with the gain region and the external optical cavity are arranged so that a spectral ratio between the Half Width Half Maximum (HWHM) spectral bandwidth of the modal gain and a free spectral range of the external cavity in the range of 2 to 50.

Abstract: A laser device for generating an optical wave including at least two frequencies, such laser device including: a first element including a gain region, a second mirror, distinct from the first element, and arranged so as to form with a first mirror an optical cavity including the gain region; means for pumping the gain region so as to generate the optical wave; means for shaping the light intensity of the optical wave arranged for selecting at least two transverse modes of the optical wave; and means for shaping the longitudinal and/or transversal phase profile of the optical wave and arranged for adjusting at least two transverse modes of the optical wave.

Abstract: A laser device is provided for generating an optical wave at a laser frequency, including (i) a semiconductor element having a gain region with quantum wells, the gain region being located between a first mirror and an exit region defining an optical microcavity, (ii) a second mirror distinct from the semiconductor element and arranged so as to form with the first mirror an external optical cavity including the gain region, (iii) a pump for pumping the gain region so as to generate the optical wave, wherein the optical microcavity with the gain region and the external optical cavity are arranged so that a spectral ratio between the Half Width Half Maximum (HWHM) spectral bandwidth of the modal gain and a free spectral range of the external cavity in the range of 2 to 50.

Abstract: An optical fiber transmitter for emitting an information-carrying laser beam comprises an optically or electrically pumped single mode MQW (multi-quantum well) semiconductor amplifying mirror as a gain medium and a separate external reflector to form a cavity. The external cavity length defines a comb of optical modes, all or a subset of which correspond to channel wavelengths of an optical telecommunications system having plural optical channels. The semiconductor gain element has a homogeneously broadened gain region; a tuning arrangement tunes the laser from mode to mode across the gain region, thereby selecting each one of the plural optical channels. When the maximum gain bandwidth is less than mode-to-mode spacing defined by the cavity, the tuning arrangement includes a means of altering the temperature of the amplifying mirror, thereby translating the frequency of the gain peak from one mode to another.

Abstract: An optical fiber transmitter comprises an optically pumped single mode MQW VECSEL for emitting an information-carrying laser beam and has an external cavity length defining a comb of optical modes, each mode corresponding to a channel wavelength of an optical telecommunications system having plural optical channels. A semiconductor structure of the VECSEL has an optical-pump-excited multiple quantum well (MQW) homogeneously broadened gain region active over a band which is less than mode-to-mode spacing, the gain region being tunable to hop from a first mode to an adjacent second mode. A tuning arrangement tunes the VECSEL from mode to mode thereby to select each one of the plural optical channels. An optical modulator adds modulation to a beam emitting from the laser to provide the information-carrying laser beam, and a coupler couples the information-carrying laser beam into an optical fiber of the optical telecommunications system.

Abstract: An optical fiber transmitter for emitting an information-carrying laser beam comprises an optically or electrically pumped single mode MQW (multi-quantum well) semiconductor amplifying mirror as a gain medium and a separate external reflector to form a cavity. The external cavity length defines a comb of optical modes, all or a subset of which correspond to channel wavelengths of an optical telecommunications system having plural optical channels. The semiconductor gain element has a homogeneously broadened gain region; a tuning arrangement tunes the laser from mode to mode across the gain region, thereby selecting each one of the plural optical channels. When the maximum gain bandwidth is less than mode-to-mode spacing defined by the cavity, the tuning arrangement includes a means of altering the temperature of the amplifying mirror, thereby translating the frequency of the gain peak from one mode to another.

Abstract: A laser suitable for intra-cavity laser absorption spectroscopy and for telecommunication system comprises a Bragg mirror, a multiple quantum well active region and an anti-reflective coating together with a second mirror spaced from the coating to define an external cavity, the free spectral range of the sub-cavity defined by the coating and the active region being less than two times the bandwidth of the coating and the bandwidth of the Bragg mirror being at least as great as the free spectral range of the sub-cavity.

Abstract: An optical fiber transmitter for emitting an information-carrying laser beam comprises an optically or electrically pumped single mode MQW (multi quantum well) semiconductor amplifying mirror as a gain medium and a separate external reflector to form a cavity. The external cavity length defines a comb of optical modes, all or a subset of which corresponding to channel wavelengths of an optical telecommunications system having plural optical channels. The semiconductor gain element has a homogeneously broadened gain region; a tuning arrangement tunes the laser from mode to mode across the gain region thereby selecting each one of the plural optical channels. When the maximum gain bandwidth is less than mode-to-mode spacing defined by the cavity, that tuning arrangement comprises a means of altering the temperature of the amplifying mirror, thereby translating the frequency of the gain peak from one mode to another.

Abstract: A laser suitable for intra-cavity laser absorption spectroscopy and for telecommunication system comprises a Bragg mirror, a multiple quantum well active region and an anti-reflective coating together with a second mirror spaced from the coating to define an external cavity, the free spectral range of the sub-cavity defined by the coating and the active region being less than two times the bandwidth of the coating and the bandwidth of the Bragg mirror being at least as great as the free spectral range of the sub-cavity.