Chern character for matrix factorizations via Chern-Weil

Given a matrix factorization, we use the Atiyah class to give an algebraic Chern-Weil type construction to its Chern character; this allows us to realize the Chern character in an explicit way. It also generalizes the existing result to any smooth $k$-algebra $Q$ ($k$ a commutative ring containing $\mathbb{Q}$) and any $f\in Q$, which agrees with a recent result of Platt. We also study some basic properties of the Chern character.