  We begin this thesis by expanding the technique of teleportation simulation,
which adds noise to the entangled resource state to mimic channel effects. By
introducing classical noise in the communication step, we show it is possible
to simulate more than just Pauli channels using teleportation. This new class
is characterised, and studied in detail for a particular resource state,
leading to a family of simulable channels named "Pauli-Damping channels" whose
properties are analysed.
  Also introduced are a new family of quantum states, "phase Werner" states,
whose entanglement properties relate to the interesting conjecture of bound
entangled states with a negative partial transpose. Holevo-Werner channels, to
which these states are connected, are shown to be teleportation covariant. We
exploit this to present several interesting results, including the optimal
estimation of the channel-defining parameter. The minimal binary-discrimination
error for Holevo-Werner channels is bounded for the first time with the
analytical form of the quantum Chernoff bound. We also consider the secret key
capacity of these channels, showing how different entanglement measures provide
a better upper bound for different regions of these channels.
  Finally, a method for generating new Bell inequalities is presented,
exploiting nonphysical probability distributions to obtain new inequalities.
Tens of thousands of new inequivalent inequalities are generated, and their
usefulness in closing the detection loophole for imperfect detectors is
examined, with comparison to the current optimal construction. Two candidate
Bell inequalities which may equal or beat the best construction are presented.
