Abstract: An optical scanning microscope includes an illumination system (160) and an objective lens (134) operable together to provide the excitation radiation (152, 154) in a focal volume (124) at sufficient intensity to cause emission of emission radiation from a sample in the focal volume. The objective lens (134) is scanned by an objective scanner (130, 132). In this example an x-y transducer (xyXD) (130) is connected to a kinematic flexure mechanism (132) which acts as a scanning lens mount. The kinematic flexure mechanism is operable to scan the objective in two dimensions transverse with respect to the objective's optical axis so as to scan the emitting focal volume in corresponding dimensions. The kinematic flexure mechanism may be a unitary 3D-printed member.

Abstract: An optical scanning microscope includes an illumination system (160) and an objective lens (134) operable together to provide the excitation radiation (152), (154) in a focal volume (124) at sufficient intensity to cause non-linear emission of emission radiation from a sample in the focal volume. The objective is an aspheric objective configured to focus the excitation radiation without, or with minimal, spherical aberration. The objective lens (134) is scanned by an objective scanner (130), (132). In this example an x-y transducer (xyXD) (130) is connected to a kinematic flexure mechanism (132) which acts as a scanning lens mount. The objective scanner (130), (132) is operable to scan the objective (134) in two dimensions transverse with respect to the objective's optical axis so as to scan the emitting focal volume (124) in corresponding dimensions.

Abstract: An optical scanning microscope includes an illumination system (160) and an objective lens (134) operable together to provide the excitation radiation (152, 154) in a focal volume (124) at sufficient intensity to cause emission of emission radiation from a sample in the focal volume. The objective lens (134) is scanned by an objective scanner (130, 132). In this example an x-y transducer (xyXD) (130) is connected to a kinematic flexure mechanism (132) which acts as a scanning lens mount. The kinematic flexure mechanism is operable to scan the objective in two dimensions transverse with respect to the objective's optical axis so as to scan the emitting focal volume in corresponding dimensions. The kinematic flexure mechanism may be a unitary 3D-printed member.

Abstract: A mode locking semiconductor disk laser (SDL) comprising a resonator terminated by first and second mirrors and folded by a third mirror is presented. The third mirror includes a semiconductor disk laser (SDL) suitable for generating a resonator field having a predetermined central wavelength ?0, while the second mirror includes an intensity saturable mirror suitable for mode locking the resonator field at the predetermined wavelength. The central wavelength of the reflectivity profile of the first and or second mirrors is shifted to a wavelength shorter than the central wavelength ?0 to suppress gain at wavelengths longer than the central wavelength ?0. By mismatching the reflectivity profile of the first and or second mirrors to that of the desired output wavelength provides a stable mode locked laser with significantly reduced noise.

Abstract: A self mode locking laser and corresponding method is described. The laser comprises a resonator (2) terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a reflector (15) surmounted by a multilayer semiconductor gain medium (16) that includes at least one quantum well layer and an optical Kerr lensing layer (20). A perturbator is also included that provides a means to induce a perturbation on an intensity of one or more cavity modes of the resonator. The pertubator is employed to induce a small perturbation on the intensity of the cavity modes of the resonator which is sufficient for the optical Kerr lensing layer to induce mode locking on the output field. The second mirror (4) comprises an intensity saturable mirror that provides a means for reducing the pulse widths of the generated output field e.g. to around 100 fs.

Abstract: An optical amplifier is described. The optical amplifier (1) comprises a semiconductor disk gain medium (2) including at least one quantum well layer (9) and a pump field source (17) for generating an optical pump field (3) for the semiconductor disk gain medium. The optical amplifier acts to generate an output optical field (5) from an input optical field (4) received by the optical amplifier and arranged to be incident upon the semiconductor disk gain medium. Employing a semiconductor disk gain medium within the optical amplifier allows it to be optically pumped and thus provided for increased stability and beam quality of the output optical field while allowing for the design of optical amplifiers which can operate across a broad range of wavelengths. The optical amplifier may be employed with continuous wave or pulsed input optical fields.

Abstract: A passively mode-locking laser and corresponding method is described. The laser comprises a resonator (2) terminated by first (3) and second (4) mirrors and folded by a third (5) and fourth (6) mirror. The third mirror comprises a reflector (14) surmounted by a multilayer semiconductor gain medium (15) including at least one quantum well layer while the second mirror (4) comprises an intensity saturable mirror. The resonator is configured to provide a cross sectional area of an intra cavity resonating field on the intensity saturable mirror that is greater than or equal to a cross sectional area of the intra cavity resonating field on the multilayer semiconductor gain medium. This arrangement provides a passively mode-locking laser that exhibits increased stability when compared to those systems known in the art.

Abstract: The present invention describes a method and apparatus for mounting a semiconductor disc laser (SDL). In particular there is described a cooling apparatus assembly (12) for mounting the semiconductor disc laser (1) the cooling apparatus assembly comprising a crystalline heat spreader (8) made of diamond, sapphire or SiC and optically contacted to the SDL (1). The apparatus further comprises a heatsink (13) made of copper and a recess (16) located on a first surface (15) of the heatsink. A pliable filler material (17) which may be In or an In alloy is provided within the recess (16) such that when a sealing plate (19) is fastened to the heatsink the SDL (1) is hermetically sealed within the recess. Hermetically sealing the SDL within the recess is found to significantly increase the lifetime of the device comprising the SDL. The heat sink (13) may be water cooled with pipes (14) delivering the water. In case the sealing plate (19) is made from for example Invar, it has an aperture (20).

Abstract: A passively mode-locking laser and corresponding method is described. The laser comprises a resonator (2) terminated by first (3) and second (4) mirrors and folded by a third (5) and fourth (6) mirror. The third mirror comprises a reflector (14) surmounted by a multilayer semiconductor gain medium (15) including at least one quantum well layer while the second mirror (4) comprises an intensity saturable mirror. The resonator is configured to provide a cross sectional area of an intra cavity resonating field on the intensity saturable mirror that is greater than or equal to a cross sectional area of the intra cavity resonating field on the multilayer semiconductor gain medium. This arrangement provides a passively mode-locking laser that exhibits increased stability when compared to those systems known in the art.

Abstract: The present invention describes a self mode locking laser and a method for self mode locking a laser. The laser (1) comprises a resonator terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a single distributed Bragg reflector (17) upon which is mounted a multilayer semiconductor gain medium (18) and which includes at least one quantum well layer and an optical Kerr lensing layer (22). Self mode locking may be achieved by configuring the laser resonator such that the lensing effect of the Kerr lensing layer acts to reduce an astigmatism deliberately introduced to the cavity mode. The self mode locking of the laser may be further enhanced by selecting the length of the resonator such that a round trip time of a cavity mode is matched with an upper-state lifetime of one or more semiconductor carriers located within the gain medium.

Abstract: An optical amplifier is described. The optical amplifier (1) comprises a semiconductor disk gain medium (2) including at least one quantum well layer (9) and a pump field source (17) for generating an optical pump field (3) for the semiconductor disk gain medium. The optical amplifier acts to generate an output optical field (5) from an input optical field (4) received by the optical amplifier and arranged to be incident upon the semiconductor disk gain medium. Employing a semiconductor disk gain medium within the optical amplifier allows it to be optically pumped and thus provided for increased stability and beam quality of the output optical field while allowing for the design of optical amplifiers which can operate across a broad range of wavelengths. The optical amplifier may be employed with continuous wave or pulsed input optical fields.

Abstract: A self mode locking laser and corresponding method is described. The laser comprises a resonator (2) terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a reflector (15) surmounted by a multilayer semiconductor gain medium (16) that includes at least one quantum well layer and an optical Kerr lensing layer (20). A perturbator is also included that provides a means to induce a perturbation on an intensity of one or more cavity modes of the resonator. The pertubator is employed to induce a small perturbation on the intensity of the cavity modes of the resonator which is sufficient for the optical Kerr lensing layer to induce mode locking on the output field. The second mirror (4) comprises an intensity saturable mirror that provides a means for reducing the pulse widths of the generated output field e.g. to around 100 fs.

Abstract: The present invention describes a self mode locking laser and a method for self mode locking a laser. The laser (1) comprises a resonator terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a single distributed Bragg reflector (17) upon which is mounted a multilayer semiconductor gain medium (18) and which includes at least one quantum well layer and an optical Kerr lensing layer (22). Self mode locking may be achieved by configuring the laser resonator such that the lensing effect of the Kerr lensing layer acts to reduce an astigmatism deliberately introduced to the cavity mode. The self mode locking of the laser may be further enhanced by selecting the length of the resonator such that a round trip time of a cavity mode is matched with an upper-state lifetime of one or more semiconductor carriers located within the gain medium.

Abstract: The present invention describes a mode locking semiconductor disk laser (SDL). The laser comprises a resonator terminated by first and second mirrors (6,7) and folded by a third mirror. The third mirror or comprising a semiconductor disk laser (8) suitable for generating a resonator field comprising a predetermined central wavelength A0 while the second mirror comprising an intensity saturable mirror (7) suitable for mode locking the resonator field at the predetermined wavelength. The reflectivity of the of the resonator at the central wavelength A0 is reduced by shifting the reflectivity profiles of the first and or second mirrors to wavelength shorter than the predetermined wavelength so as to suppress gain at wavelengths longer than the central wavelength A0. By mismatching the reflectivity profile (32) of the second mirror (7) to that of the desired output wavelength (3) provides a stable mode locked laser with significantly reduced noise.

Abstract: The present invention describes a method and apparatus for mounting a semiconductor disc laser (SDL). In particular there is described a cooling apparatus assembly (12) for mounting the semiconductor disc laser (1) the cooling apparatus assembly comprising a crystalline heat spreader (8) made of diamond, sapphire or SiC and optically contacted to the SDL (1). The apparatus further comprises a heatsink (13) made of copper and a recess (16) located on a first surface (15) of the heatsink. A pliable filler material (17) which may be In or an In alloy is provided within the recess (16) such that when a sealing plate (19) is fastened to the heatsink the SDL (1) is hermetically sealed within the recess. Hermetically sealing the SDL within the recess is found to significantly increase the lifetime of the device comprising the SDL. The heat sink (13) may be water cooled with pipes (14) delivering the water. In case the sealing plate (19) is made from for example Invar, it has an aperture (20).

Abstract: The present invention describes a self mode locking laser and a method for self mode locking a laser. The laser (1) comprises a resonator terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a single distributed Bragg reflector (17) upon which is mounted a multilayer semiconductor gain medium (18) and which includes at least one quantum well layer and an optical Kerr lensing layer (22). Self mode locking may be achieved by configuring the laser resonator such that the lensing effect of the Kerr lensing layer acts to reduce an astigmatism deliberately introduced to the cavity mode. The self mode locking of the laser may be further enhanced by selecting the length of the resonator such that a round trip time of a cavity mode is matched with an upper-state lifetime of one or more semiconductor carriers located within the gain medium.

Abstract: The present invention describes a self mode locking laser and a method for self mode locking a laser. The laser (1) comprises a resonator terminated by first (3) and second (4) mirrors and folded by a third mirror (5). The third mirror comprises a single distributed Bragg reflector (17) upon which is mounted a multilayer semiconductor gain medium (18) and which includes at least one quantum well layer and an optical Kerr lensing layer (22). Self mode locking may be achieved by configuring the laser resonator such that the lensing effect of the Kerr lensing layer acts to reduce an astigmatism deliberately introduced to the cavity mode. The self mode locking of the laser may be further enhanced by selecting the length of the resonator such that a round trip time of a cavity mode is matched with an upper-state lifetime of one or more semiconductor carriers located within the gain medium.

Abstract: There is disclosed a method of manufacturing of optical devices, for example, semiconductor optoelectronic devices such as laser diodes, optical modulators, optical amplifiers, optical switches, and the like. There is further disclosed Optoelectronic Integrated Circuits (OEICs) and Photonic Integrated Circuits (PICs) including such devices. According to the present invention there is provided a method of manufacturing an optical device (40), a device body portion (15) from which the device (40) is to be made including a Quantum Well Intermixing (QWI) structure (30), the method including the step of plasma etching at least part of a surface of the device body portion (5) prior to depositing a dielectric layer (51) thereon so as to introduce structural defects at least into a portion (53) of the device body portion (5) adjacent the dielectric layer (51). The structural defects substanially comprise “point” defects.

Abstract: There is disclosed an improved optical device (110), such as a laser, modulator, amplifier, switch, ore the like. The invention provides an optically active device (110) comprising: an optically active region (150) having an input/output end (165); and an optically passive region (155, 160) extending from said input/output end (165, 170) of the optically active region (150) an input/output end (175, 180) of the device (110).

Abstract: There is disclosed an improved semiconductor laser device (10). Previous high power (greater than a few hundred milliwatts output) semiconductor lasers suffer from a number of problems such as poor beam quality and low brightness. The invention therefore provides a semiconductor laser device (10) including at least one portion which has been Quantum Well Intermixed (QWI) and means for providing gain profiling within an active portion of the device (10). In a preferred implementation the device (10) provides a Wide Optical Waveguide (WOW).