Experimental demonstration of quantum data compression

We present experimental results implementing the Quantum Schur-Weyl Transform QSWT for three qubits, allowing us to compress three quantum bits into two. In our implementation the three qubits are encoded in two photons. The first photon encodes a path and a polarization qubit, while the second photon encodes a single polarization qubit. We use the QSWT to map all of the information from the 3 qubits onto the path and polarization qubits encoded in the first photon, allowing us to discard the second photon. We characterize our compression by performing measurements on the remaining two qubits and show that they obey the statistics of a three qubit system. We expect our technique to become extremely useful in the near future, for all quantum information architectures, as few qubit quantum memories become available.