Systems, apparatuses, and methods for optical focusing in scattering samples

A system, comprising:

• a magnet to apply, to a sample exhibiting optical scattering and having a plurality of emission particles distributed therein that exhibit spin-dependent fluorescence, a magnetic field to shift a resonance frequency of each emission particle of the plurality of emission particles in a position-dependent manner;
• a microwave generator to generate and apply a microwave signal to the sample to modulate the spin state of at least one emission particle of the plurality of emission particles;
• a light source to excite the sample with an excitation beam, such that the excitation beam causes at least one emission particle of the plurality of emission particles to emit spin-dependent fluorescence;
• a detector to detect the spin-dependent fluorescence;
• and
• a controller to:
• estimate a position of the at least one of the plurality of emission particles within the sample based on the spin-dependent fluorescence, the resonance frequency of the at least one of the plurality of emission particles, and the magnetic field;
• and
• estimate optical transmission information for the sample based on a wavefront of the excitation beam and the estimated position, the optical transmission information including a measure of an optical field at each position of an emission particle of the plurality of emission particles.

A system, comprising:

• a magnet, in electromagnetic communication with a sample exhibiting optical scattering and having a plurality of diamond nanoparticles distributed therein with nitrogen vacancy centers that exhibit spin-dependent fluorescence, to apply a magnetic field having a gradient, such that the magnetic field shifts a resonance frequency of each nitrogen vacancy center in the plurality of diamond nanoparticles based on a position of that nitrogen vacancy center in the sample;
• a light source to emit an excitation beam;
• a wavefront shaping device, in optical communication with the light source and the sample, to excite the sample with the excitation beam, the excitation beam including a set of basis modes, such that the excitation beam causes at least one nitrogen vacancy center in the plurality of diamond nanoparticles to emit spin-dependent fluorescence;
• a detector, in optical communication with the sample, to detect the spin-dependent fluorescence emitted by the sample;
• and
• a controller, operably coupled to the detector and the wavefront shaping device, to:
• estimate a position of the at least one nitrogen vacancy center in the plurality of diamond nanoparticles within the sample based on the spin-dependent fluorescence, the resonance frequency of the at least one nitrogen vacancy center in the plurality of diamond nanoparticles, and the magnetic field;
• generating an optical transmission matrix for the sample based on a wavefront of the excitation beam and the estimated position, the optical transmission matrix including a measure of an optical field at a position of each nitrogen vacancy center in the plurality of diamond nanoparticles, and for each basis mode of the set of basis modes;
• estimate, for the position of each nitrogen vacancy center in the plurality of diamond nanoparticles and for each basis mode, a feedback parameter to generate a set of feedback parameters;
• and
• actuate the wavefront shaping device to modify at least one characteristic of at least one basis mode of the excitation beam based on the set of feedback parameters.