  A new transverse mode in a two-stream magnetized quantum plasma is studied by
means of a quantum hydrodynamic model, under non-relativistic and ideal Fermi
gas assumptions. It is found that Fermi pressure effects induce a minimum
cutoff wavelength for instability, unlike the classical case which is unstable
for larger wavenumbers. The external magnetic field is also shown to produce a
stabilizing effect. Conditions for the applicability of the model and specific
parameters for experimental observations are thoroughly discussed.
