We found a full analytical solution to Schrodinger equation on a simple enclosed surface: a regular tetrahedron. The time evolution of a wavefunction on it is then completely equivalent to an optical Talbot effect.
We analyze the propagation of waves on the surface of the simplest Platonic solid, the regular tetrahedron. We find that the time evolution of a quantum particle confined to such a surface is equivalent to the diffraction pattern from a certain grating profile and can therefore be investigated in a simple diffraction experiment. The quantum particle exhibits perfect quantum state revivals, which translate into the fractional Talbot effect in the diffraction pattern. We present the results of such an experiment and compare them with numerical simulations.
The quantum mechanical description of phase remains a fundamental challenge, with theoretical efforts tracing from the early works of London and Dirac to discrete formalisms. In this work, we extend the action-angle formalism to the Helmholtz-Schrödinger equation by introducing a phase-dependent wavefunction φ(θ,t) residing in the Hardy space H2(D). This mathematical structure, defined by functions analytic on the unit disk with square-integrable boundary values, naturally ensures the positivity of the energy spectrum while providing a rigorous framework for wave dynamics in photonic systems. We demonstrate that establishing a self-adjoint phase operator requires extending the Hilbert space to L2, a procedure that necessitates the admission of negative energy states. We interpret these states through an analogy with the Dirac sea, where the existence of antiphase or antiphoton modes provides a conceptual framework for understanding the fundamental limits of phase localization and quantum uncertainty. This formalism is applied to light propagation in multimode waveguides characterized by anharmonic refractive index profiles. By mapping modal dispersion to our phase representation, we show that the deviation of propagation constants from linear spacing governs the spatial evolution of the optical field. This approach offers a clear mechanism for the emergence of periodic self-imaging known as the Talbot effect, the generation of fractional revivals, and the formation of complex fractal interference patterns, providing a robust toolkit for the characterization and design of multimode interference devices.
Talbot effect in the space-time evolution of matter waves is analyzed and shown that the matter waves at relativistic and non-relativistic velocities exhibit coherence beyond the grating and display Talbot self-imaging. The grating is realized by considering equidistant narrowly peaked coherent probability distributions at the onset. Theoretical frame work is based on a quantum particle at relativistic and non-relativistic velocities in a one dimensional box. The matter waves, in their evolution, display Talbot self-imaging and fractional self-imaging as restructuring, respectively, at Talbot length and fractional Talbot lengths.