Thursday, November 20, 2003

**Quantum cnot Gate Created...This Time With Photons**

For the second time in three weeks, Nature has a paper on creation of a cnot gate. From the abstract:

*"We produce all four entangled Bell states as a function of only the input qubits' logical values, for a single operating condition of the gate. The gate is probabilistic (the qubits are destroyed upon failure), but with the addition of linear optical quantum non-demolition measurements, it is equivalent to the CNOT gate required for scalable all-optical quantum computation."*