  We investigate the migration of low-mass protoplanets embedded in dust-gas
coupled protoplanetary disks. Linear calculations are performed with respect to
the NSH (Nakagawa-Sekiya-Hayashi 1986) equilibrium within a shearing sheet. We
find that the dusty quasi-drift mode dominates the dynamical behaviors in close
proximity to the protoplanet. This mode exhibits an extremely short radial
wavelength, characterized by a dispersion relation of $ \tilde{\omega} = \left(
1 + \mu \right) \boldsymbol{W}_s \cdot \boldsymbol{k}$. The emergence of this
mode leads to a wake with a short radial length-scale ahead of protoplanets,
contributing to a positive torque, termed as ``Streaming Torque (ST)''.
Furthermore, both Lindblad torque and corotation torque are affected by the NSH
velocity. The total torque and planetary migration are contingent upon the
coupling strength between dust and gas. In most scenarios, ST predominates,
inducing outward migration for planets, thereby addressing the issue of rapid
inward migration in their formation paradigm.
