Silicon photomultipliers (SiPMs) are solid-state,
single-photon sensitive, pixelated sensors whose usage for
scintillation detection has rapidly increased over the past decade.
It is known that the avalanche process within the device, which
renders a single photon detectable, can also generate secondary
photons which may be detected by a separate device. This effect,
known as external crosstalk, could potentially degrade the science
goals of future xenon dark matter experiments. In this article, we
measure the effect of external crosstalk in a dual-phase, liquid
xenon time projection chamber fully instrumented with SiPMs. We
then consider the implications for a future xenon dark matter
experiment utilizing SiPMs and discuss possible solutions.