Geometrical optics prohibits any penetration of light into an optically rarer medium in the case of total reflection. When sandwiching, however, the rarer medium between optically denser media, a transmitted beam can be observed in the third medium. The experiment is often realized by a double-prism arrangement [1]; the effect is called frustrated total reflection due to the enforced transmission. Amazingly, the reflected and transmitted beams are shifted with respect to geometrical optics as conjectured by Newton [2] and experimentally confirmed by Goos-Hänchen 250 years later [3]. However, inconsistent results on the spatial shifts have been reported [4-7]. Here we report on measurements of the Goos-Hänchen shift in frustrated total reflection with microwaves. We found an unexpected influence of the beamwidth and angle of incidence on the shift. Our results are not in agreement with both previous experiments [6,7] and theoretical predictions [8-10]. The topic of frustrated total reflection is important for both fundamental research and applications [11-13].

Tunnelling transit time for frustrated total internal reflection (FTIR) in a double‐prism experiment was measured using microwave radiation. We have found that the transit time is of the same order of magnitude as the corresponding transit time measured either in an undersized waveguide (evanescent modes) or in a photonic lattice. Moreover we have established that in all such experiments the tunnelling transit time is approximately equal to the reciprocal (1/f) of the corresponding frequency of radiation.

The time behaviour of microwaves undergoing partial reflection by photonic barriers was measured in the time and in the frequency domain. It was observed that unlike the duration of partial reflection by dielectric layers, the measured reflection duration of barriers is independent of their length. The experimental results point to a nonlocal behaviour of evanescent modes at least over a distance of some ten wavelengths. Evanescent modes correspond to photonic tunnelling in quantum mechanics.

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If a quantum mechanical particle is scattered by a potential well, the wave function of the particle can propagate with negative phase time.Due to the analogy of the Schrödinger and the Helmholtz equation this phenomenon is expected to be observable for electromagnetic wave propagation. Experimental data of electromagnetic wells realized by wave guides filled with different dielectrics confirm this conjecture now.The propagation of a wave packet is determined by the dispersion relation of the medium. E.g. in vacuum a plane wave propagates with a constant amplitude and a phase shift proportional to frequency. In the case of tunnelling through a barrier, the constant phase leads to propagation speeds faster than light, calculated by [1] and measured for microwaves, single photons and infrared light [2,3,4]. In the contrary case of particles scattered by a potential well instead of a barrier, Li and Wang predicted a non-evanescent propagation but also with negative phase shifts [5]. We present here an experimental simulation of the quantum well by a microwave set-up performing the analogy between the Schrödinger and the Helmholtz equation.Applying the stationary phase approximation, the peak value of a quantum mechanical wave packet with a mean impulse p 0 =hk 0 propagates with the group velocity v gr =