title: Superdense coding of quantum states.
abstract: We describe a method for nonobliviously communicating a 2l-qubit quantum state by physically transmitting l+o(l) qubits, and by consuming l ebits of entanglement plus some shared random bits. In the nonoblivious scenario, the sender has a classical description of the state to be communicated. Our method can be used to communicate states that are pure or entangled with the sender's system; l+o(l) and 3l+o(l) shared random bits are sufficient, respectively.
authors.affiliation: Physics Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
authors.forename: Aram
authors.initials: A
authors.lastname: Harrow
authors.forename: Patrick
authors.initials: P
authors.lastname: Hayden
authors.forename: Debbie
authors.initials: D
authors.lastname: Leung