Lepton flavor violating Higgs boson decay at e+e- colliders

We estimate the smallest branching ratio for the Higgs decay channel h -> mu tau, which can be probed at an e(+)e(-) collider, and compare it with the projected reach at the high-luminosity run of the LHC. Using a model-independent approach, Higgs production is considered in two separate cases. In the first case, hWW and hZZ couplings are allowed to be scaled by a factor allowed by the latest experimental limits on hWW and hZZ couplings. In the second case, we have introduced higher-dimensional effective operators for these interaction vertices. Keeping BR(h -> mu tau) as a purely phenomenological quantity, we find that this branching ratio can be probed down to approximate to 2.69 x 10(-3) and approximate to 5.83 x 10(-4), respectively, at the 250 GeV and 1000 GeV runs of an e(+)e(-) collider.