In this work, intersubband transitions in meta-stable cubic AlN/GaN and AlxGa1-xN/GaN superlattices are studied. The samples were grown using plasma assisted molecular beam epitaxy on 3C-SiC substrates.It was possible to estimate layer thicknesses with an accuracy of 1 monolayer using X-ray diffraction and simulations of the diffraction profile. Furthermore transmission electron microscopy was performed in order to investigate the structural quality of the epitaxial layers. Large areas show high crystalline quality and reproducible superlattice growth.For optical characterization, photoluminescence, cathodoluminescence and Fourier transform infrared spectroscopy was used.Resonant tunneling through Al(Ga)N/GaN double barrier structures, grown on free standing 3C-SiC substrates, with peak-to-valley ratios between 1.3 and 2.7 was measured at low and room temperature.The intersubband transition energy in Al(Ga)N/GaN superlattices could be tuned over a large spectral range. It was possible to obtain the longest and shortest wavelength of intersubband transitions ever reported in cubic nitrides (62.5 um - 1.55 um).The conduction band offset between GaN and AlN was determined to (1.4 0.1) eV and a valence band offset of (0.5 0.1) eV is obtained.First infrared absorption was measured in asymmetric coupled AlN/GaN multi-quantum-wells. Model calculations show the possibility to reach the 1.55 um region with such devices.