Factorisation of two-variable p-adic L-functions

Let $f$ be a modular form which is non-ordinary at $p$. Kim and Loeffler have recently constructed two-variable $p$-adic $L$-functions associated to $f$. In the case where $a_p=0$, they showed that, as in the one-variable case, Pollack’s plus and minus splitting applies to these new objects. In this short note, we show that such a splitting can be generalised to the case where $a_p\mathrm{\ne }0$ using Sprung’s logarithmic matrix.