Lensing signals from Spin-2 perturbations
  We compute the angular power spectra of the E-type and B-type lensing
potentials for gravitational waves from inflation and for tensor perturbations
induced by scalar perturbations. We derive the tensor-lensed CMB power spectra
for both cases. We also apply our formalism to determine the linear lensing
potential for a Bianchi I spacetime with small anisotropy.
