The evolution of thin current sheet with anti-parallel and guided magnetic fields is considered by means of numerical simulations of Vlasov-Maxwell equations in six-dimensional phase space. It is found that the unstable lower-hybrid-drift (LHD) waves excited at the edges of the sheet resonantly interact with the ion flow through the inverse Landau resonance. The LHD modes from the opposite edges gradually penetrate towards the current sheet center and trigger a global instability of the sheet. The resulting global mode has the frequency and wavelength of the LHD but the growth rate of the order of ion gyrofrequency. In the anti-parallel fields case the global wave-mode directly couples to the tearing-mode instability and enhances magnetic reconnection. In the guided field case the instability of obliquely propagating LHD modes becomes weaker with increasing guide-field strength due to the lack of resonant ions and can no longer couple to the global oscillations of the current sheet.
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