Researchers create dispersion-assisted photodetector to decipher high-dim light

Angular quantities "wrap around" such that `divmod(angle_theta, 2*pi) == n_rotations, angular displacement from zero`; and IIRC all phase spaces must too?

Optical phase space: https://en.wikipedia.org/wiki/Optical_phase_space

If it is possible to estimate photonic phase given intensity, how much more useful is a phase sensor than the existing intensity sensors?

From "Bridging coherence optics and classical mechanics: A generic light polarization-entanglement complementary relation":

> A generic complementary identity relation is obtained for arbitrary light fields. More surprisingly, through the barycentric coordinate system, optical polarization, entanglement, and their identity relation are shown to be quantitatively associated with the mechanical concepts of center of mass and moment of inertia via the Huygens-Steiner theorem for rigid body rotation. The obtained result bridges coherence wave optics and classical mechanics through the two theories of Huygens.

There are various patterns of polarization, relative to a signal origin IIUC:

Polarization (waves) https://en.wikipedia.org/wiki/Polarization_(waves)

Types of polarization: Linear, Elliptical, and Circular; and also Radial and Azimuthal polarization

Radial polarization: https://en.wikipedia.org/wiki/Radial_polarization :

> Beams with radial and azimuthal polarization are included in the class of cylindrical vector beams. [7]

> A radially polarized beam can be used to produce a smaller focused spot than a more conventional linearly or circularly polarized beam, [8] and has uses in optical trapping. [9]

> It has been shown that a radially polarized beam can be used to increase the information capacity of free space optical communication via mode division multiplexing, [10] and radial polarization can "self-heal" when obstructed. [11]

Vector fields in cylindrical and spherical coordinates: Todo

Laser beam profiler: https://en.wikipedia.org/wiki/Laser_beam_profiler

Gaussian beam ... Quasioptics || Geometrical optics with rays and arcs: https://en.wikipedia.org/wiki/Gaussian_beam :

> Fundamentally, the Gaussian is a solution of the axial Helmholtz equation, the wave equation for an electromagnetic field. Although there exist other solutions, the Gaussian families of solutions are useful for problems involving compact beams.

Photonic integrated circuit: https://en.wikipedia.org/wiki/Photonic_integrated_circuit :

> A photonic integrated circuit (PIC) or integrated optical circuit is a microchip containing two or more photonic components that form a functioning circuit. This technology detects, generates, transports, and processes light. Photonic integrated circuits utilize photons (or particles of light) as opposed to electrons that are utilized by electronic integrated circuits.