  We study characteristics of superpositions and entanglement of thermal states
at high temperatures and discuss their applications to quantum information
processing. We introduce thermal-state qubits and thermal-Bell states, which
are a generalization of pure-state qubits and Bell states to thermal mixtures.
A scheme is then presented to discriminate between the four thermal-Bell states
without photon number resolving detection but with Kerr nonlinear interactions
and two single-photon detectors. This enables one to perform quantum
teleportation and gate operations for quantum computation with thermal-state
qubits.
