can we obtain light amplification in the absence of stimulated emission
Answers
No we can't obtain okk
Yes and no. It depends on what you mean. If you're being very strict with the definition, then the name “laser” or “Light Amplification by Stimulated Emission of Radiation” precludes laser light coming from any other source.
If you're just looking for a source of coherent light, then yes, there are many ways to avoid a traditional atomic gain medium that employs stimulated emission from excited atoms. Another answer already references one way called “optical parametric amplification,” (OPA) which is a nonlinear process that amplifies a “seed” light pulse.
A seed photon catalyzes the splitting of a high energy photon into two daughter photons - one at the energy of the original pulse and one carrying the leftover energy.
A free-electron laser does not use an atomic gain medium, it instead uses an electron beam that is wiggled back and forth (literally, the device is called a wiggler) at a certain frequency, and emits coherent light that has many of the same properties as laser light.
You can even make laser-like light by a process called “amplified spontaneous emission” (ASE) in normal lasers. It's actually a main limitation of certain lasers, where instead of the laser pulse getting amplified, you amplify noise in the gain medium and it washes out your laser pulse. It's not always a bad thing, there are many ASE light sources sold, and they're very useful.