Strongly lensed extreme mass-ratio inspirals

In this Letter, we investigate detection rates and parameter estimation of strongly-lensed extreme mass-ratio inspirals (LEMRIs) in the context of the Laser Interferometer Space Antenna (LISA). Our results indicate that LEMRIs constitute a new gravitational-wave target signal for LISA, with detection rates ranging from zero to $\sim 40$ events over a four year-observation, and that it is possible to reveal and characterize LEMRIs at redshift $z \gtrsim 1$. We finally show that one LEMRI observation with identified host galaxy may yield percent constraints or better on the Hubble constant.