  The recent experimental realization of 1D equal Rashba-Dresselhaus spin-orbit
coupling (ERD-SOC) for cold atoms provide a disorder-free platform for the
implementation and observation of Majorana fermions (MFs), similar to the well
studied solid state nanowire/superconductor heterostructures. However, the
corresponding 1D chains of cold atoms possess strong quantum fluctuation, which
may destroy the superfluids and MFs. In this Letter, we show that such 1D
topological chains with MFs may be on demand generated in a 2D non-topological
optical lattice with 1D ERD-SOC by modifying local potentials on target
locations using experimentally already implemented atomic gas microscopes or
patterned (e.g., double or triple well) optical lattices. All ingredients in
our scheme have been experimentally realized and the combination of them may
pave the way for the experimental observation of MFs in a clean system.
