Abstract: A method of writing voxels to a substrate using a laser writing system comprises forming a first voxel at a first position in a substrate using a first laser pulse; detecting light emitted or scattered by the substrate as a result of forming the first voxel; determining whether the detected light satisfies a predetermined constraint; and, when the detected light does not satisfy the predetermined constraint, adjusting an amplitude of a second laser pulse. Light emission or scattering from the substrate as a result of forming a voxel is related to the properties of the formed voxel. By monitoring such emission or scattering, it is made possible to compensate for variations in performance of the laser writing system. Also provided herein are a laser writing system and computer program product which implement the method.

Abstract: A method for forming birefringent voxels comprises simultaneously generating a first seed pulse and a first data pulse. The first seed pulse and the first data pulse are spatially-separated laser pulses having different amplitudes. The first seed pulse is focused at a first seed location, and the data pulse is focused at a first data location. The first seed location and the first data location are separated by a predetermined distance along a scan path, with the first seed location being ahead of the first data location. Subsequently, a second seed pulse and a second data pulse are generated, and focused at a second seed location and second data location, respectively. The second seed and data locations are separated by the predetermined distance. The second data location is the same as the first seed location, resulting in formation of a birefringent voxel.

Abstract: An apparatus comprising: a crystal; a wire pair formed of a first wire connected so as to receive a first alternating current, and a second wire connected so as to receive a second alternating current substantially antiparallel to the first alternating current in the first wire, and located adjacent the first wire such that a localized electromagnetic filed is created in a region local to the wire pair via constructive electromagnetic interference between the first wire and the second wire in the region local to the wire pair and destructive electromagnetic field interference between the first wire and the second wire outside of the region local to the wire pair; and a colour centre located within the crystal in the region local to the wire pair.

Abstract: An apparatus comprising a crystal; at least three first wires arranged substantially parallel to each other; at least two second wires arranged substantially parallel to each other, each second wire arranged non-parallel to each first wire, such that each second wire crosses each first wire, forming at least six cross points; and at least six colour centres, each colour centre located within the crystal adjacent a different one of the at least six cross points.

Abstract: An apparatus comprising: a crystal; and a colour centre located within the crystal and adapted to receive: a magnetic field, such that a projection of the magnetic field onto a colour centre axis of the colour centre causes a change in an electron spin resonance frequency of the colour centre, and an electromagnetic signal having a frequency that substantially matches the electron spin resonance frequency of the colour centre as changed by the projection of the magnetic field onto the colour centre axis.

Abstract: Examples are disclosed that relate to efficiently producing multiple laser beams of a harmonic frequency from a fundamental frequency beam. One example provides a laser system comprising a laser configured to output a fundamental frequency beam, a first harmonic-generation stage, and a second harmonic-generation stage. The first harmonic-generation stage is configured to receive an input of the fundamental frequency beam from the laser, and output from the laser system a first-stage harmonic frequency beam and a first-stage residual fundamental frequency beam. The second harmonic-generation stage is configured to receive an input of the first-stage residual fundamental frequency beam, and to output from the laser system a second-stage harmonic frequency beam.

Abstract: One example provides a computer-implemented method for reading data stored as birefringence values in a storage medium. The method comprises acquiring an image of a voxel of the storage medium, applying a first low-pass filter with a first cutoff frequency to the image of the voxel to obtain a first background image, applying a second low-pass filter with a second cutoff frequency to the image of the voxel to obtain a second background image, the second cutoff frequency being different than the first cutoff frequency, determining an enhanced background image from the first background image and the second background image, determining birefringence values for the enhanced background image, determining birefringence values for the image of the voxel, and correcting the birefringence values for the image of the voxel based upon the birefringence values for the enhanced background image.

Abstract: One example provides a computer-implemented method for reading data stored as birefringence values in a storage medium. The method comprises acquiring an image of a voxel of the storage medium, applying a first low-pass filter with a first cutoff frequency to the image of the voxel to obtain a first background image, applying a second low-pass filter with a second cutoff frequency to the image of the voxel to obtain a second background image, the second cutoff frequency being different than the first cutoff frequency, determining an enhanced background image from the first background image and the second background image, determining birefringence values for the enhanced background image, determining birefringence values for the image of the voxel, and correcting the birefringence values for the image of the voxel based upon the birefringence values for the enhanced background image.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A method to record data in a solid substrate comprises modulating a polarization angle of a coherent optical pulsetrain, and, while the polarization angle is being modulated, focusing the coherent optical pulsetrain on a locus moving through the solid substrate at a relative velocity. Here the relative velocity, a width of the locus in a direction of the relative velocity, and a rate of modulation of the polarization angle are such that the substrate receives within the width of the locus two or more pulses of the optical pulsetrain differing in polarization angle. In this manner, the two or more pulses record, in different portions of the substrate within the width of the locus, two or more different symbols.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: An optical data-storage system comprises a laser, an imaging optic, and associated computer logic. The laser is configured to emit a pulsed wavefront having uniform phase and polarization. The imaging optic is configured to modulate the phase and polarization of different portions of the wavefront by different amounts, and to diffract light from the different portions to a substrate with writeable optical properties. The logic is configured to receive data and to control modulation of the phase and polarization such that the light diffracted from the imaging optic writes the data to the substrate.