Reflective holographic phase masks

A system comprising:

• a laser source configured to generate a coherent beam of light;
• an interferometer comprising:
• a beamsplitter to split the coherent beam into two arms;
• a phase mask in one of the two arms providing a non-uniform phase distribution in at least one direction perpendicular to a propagation direction of the coherent beam in the associated one of the two arms;
• one or more optical elements configured to combine the coherent beam from the two arms in a sample to generate an interference pattern within the sample, wherein the interference pattern corresponds to a periodic intensity variation along a grating vector and provides a non-planar lateral phase profile in at least one plane perpendicular to the grating vector, wherein at least one of a period of the intensity variation along the grating vector or an orientation of the grating vector for each of the one or more RHPMs are arranged to satisfy a Bragg condition associated with the reflection of light incident on a planar input facet of the sample back out of the input facet.

A laser system comprising:

• a gain medium configured to generate optical gain;
• a cavity surrounding the gain medium configured to generate output laser light based on the optical gain by the gain medium, wherein the cavity includes a reflective phase mask comprising:
• a solid photosensitive material having a planar input facet;
• one or more reflective holographic phase masks (RHPMs) within a volume of the solid photosensitive material, wherein a particular one of the one or more RHPMs is formed as a periodic refractive index variation of the solid photosensitive material along a grating vector normal to the input facet and further with a particular non-planar lateral phase profile in at least one plane perpendicular to the grating vector, wherein a period of the refractive index variation along the grating vector for each of the one or more RHPMs is arranged to retroreflect via Bragg diffraction light of a particular wavelength, wherein a phase distribution of the retroreflected light is modified by the non-planar lateral phase profiles of the one or more RHPMs, wherein optical modes of the output laser light associated with the wavelengths retroreflected by the one or more RHPMs are determined by the non-planar lateral phase profiles of the associated RHPMs.

A system comprising:

• two or more transmitters configured to generate modulated light beams at two or more wavelengths;
• a multiplexer configured to receive the modulated light beams and direct the modulated beams along a transmission pathway;
• two or more detectors;
• and
• a demultiplexer configured to receive the modulated light beams from the transmission pathway and direct the modulated light beams along separate paths to the two or more detectors;
• one or more phase transformation devices comprising:
• a solid photosensitive material having a planar input facet;
• and
• two or more reflective holographic phase masks (RHPMs) within a volume of the solid photosensitive material, wherein a particular one of the two or more RHPMs is formed as a periodic refractive index variation of the solid photosensitive material along a particular grating vector and further with a particular non-planar lateral phase profile in at least one plane perpendicular to the particular grating vector, wherein at least one of a period of the refractive index variation along the grating vector or an orientation of the grating vector for each of the two or more RHPMs are arranged to reflect light incident on the input facet that satisfies a Bragg condition, wherein a phase distribution of the reflected light is modified by the non-planar lateral phase profiles of the associated one or more RHPMs;
• wherein at least one of the one or more phase transformation devices is configured to operate as at least one of the multiplexer or the demultiplexer.