  We study the phase diagram of a two-dimensional ultracold Fermi gas with the
synthetic spin-orbit coupling (SOC) that has recently been realized at NIST.
Due to the coexistence of anisotropic SOC and effective Zeeman fields in the
NIST scheme, the system shows rich structure of phase separation involving
exotic gapless superfluid and Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) pairing
states with different center-of-mass momentum. In particular, we characterize
the stability region of FFLO states and demonstrate their unique features under
SOC. We then show that the effective transverse Zeeman field in the NIST scheme
can qualitatively change the landscape of the thermodynamic potential which
leads to intriguing effects such as the disappearance of pairing instability,
the competition between different FFLO states, and the stabilization of a fully
gapped FFLO state. These interesting features may be probed for example by
measuring the in-situ density profiles or by the momentum-resolved
radio-frequency spectroscopy.
