We prove that Hermitian cusp forms of weight $k$ for the Hermitian modular group of degree 2 are determined by their Fourier coefficients indexed by matrices whose determinants are essentially square-free. Moreover, we give a quantitative version of the above result. This is a consequence of the corresponding results for integral weight elliptic cusp forms, which are also treated in this paper.
Pramath Anamby. Soumya Das. "Distinguishing Hermitian cusp forms of degree 2 by a certain subset of all Fourier coefficients." Publ. Mat. 63 (1) 307 - 341, 2019. https://doi.org/10.5565/PUBLMAT6311911