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Let $X$ be a quasi-projective scheme, the followings are quite useful.

  1. Every coherent sheaf is globally generated after tensoring with a suitable line bundle.
  2. Every coherent sheaf has trivial higher cohomology groups after tensoring with a suitable line bundle.
  3. Every coherent sheaf is a quotient of a finite rank locally free sheaf.

Question Are there any analogous discussions for Deligne- Mumford/Artin Stacks. My primary interests would be on the stacks of principal bundles/Higgs bundles on a curve. Thank you in advance.

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About 1 & 2, I doubt there are sensible results without some hypothesis like the existence an ample family of line bundles that makes the stack actually a scheme, in fact a so-called divisorial scheme.

As for 3, there is a paper that settles the issue, namely a quasi-compact and quasi-separated algebraic stack has affine stabilizer groups at closed points and satisfies the resolution property if and only if it is the quotient stack of a quasi-affine scheme by an action of $\mathop{GL}(n)$ for some $n$.

It is: Gross, Philipp: Tensor generators on schemes and stacks. Algebr. Geom. 4 (2017), no. 4, 501–522.

ArXiv version: https://arxiv.org/abs/1306.5418

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Tame Artin stacks (in the sense of Abramovich, Olsson and Vistoli, https://math.berkeley.edu/~molsson/tame.pdf) with quasi-projective moduli spaces will have property 2: the line bundle is the pullback of an ample line bundle on the moduli space.

As to property 1, a line bundle will not be enough, but you can get a version for quotient tame Artin stacks using a generating sheaf (in the sense of Olsson and Starr, https://math.berkeley.edu/~molsson/quot2a.pdf).

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