  We analytically determine the non-Hermitian mobility edges of a
one-dimensional quasiperiodic lattice model with exponential decaying hopping
and complex potentials as well as its dual model, which is just a non-Hermitian
generalization of the Ganeshan-Pixley-Das Sarma model with nonreciprocal
nearest-neighboring hopping. The presence of non-Hermitian term destroys the
self-duality symmetry and thus prevents us exploring the
localization-delocalization point through looking for self-dual points.
Nevertheless, by applying Avila's global theory, the Lyapunov exponent of the
Ganeshan-Pixley-Das Sarma model can be exactly derived, which enables us to get
an analytical expression of mobility edge of the non-Hermitian dual model.
Consequently, the mobility edge of the original model is obtained by using the
dual transformation, which creates exact mappings between the spectra and
wavefunctions of these two models.
