  Microstrata are the non-extremal analogues of superstrata: they are smooth,
non-extremal (non-BPS) solitonic solutions to IIB supergravity whose
deep-throat limits approximate black holes. Using perturbation theory and
numerical methods, we construct families of solutions using a consistent
truncation to three-dimensional supergravity. The most general families
presented here involve two continuous parameters, or amplitudes, and four
quantized parameters that set the angular momenta and energy levels. Our
solutions are asymptotic to the vacuum of the D1-D5 system: AdS$_3 \times S^3
\times T^4$. Using holography, we show that the they are dual to multi-particle
states in the D1-D5 CFT involving a large number of mutually non-BPS
supergravitons and we determine the anomalous dimensions of these states from
the binding energies in supergravity. These binding energies are uniformly
negative and depend non-linearly on the amplitudes of the states. In one family
of solutions, smoothness restricts some of the fields to lie on a special locus
of the parameter space. Using precision holography we show that this special
locus can be identified with the multi-particle states constructed via the
standard OPE of the single-particle constituents. Our numerical analysis shows
that microstrata are robust at large amplitudes and the solutions can be
obtained to very high precision.
