Here we are speaking of the holy grail of computing and we aren’t talking a new Apple Air or Xbox 360, as this is Quantum computing my friends. However for some reason it has turned out to be a more of challenge then even the likes of Gordon Moore could have guessed as just so happens to rely on encoding information in quantum bits (qubits) that have two fundamental properties about them. The first is that of coherence , which enable qubit states to naturally change in a syncronized manner. Where the second is even more out there being that of quantum entanglement whose role in the mix is to correlate the states of different qubits with one another.
The idea is when an operation is performed and measurements on a qubit taken that it is entangled with another qubit, allowing us to automatically learn about as well as modify the state of its partner. This creates a state of quasi-parallelism which allows a quantum based system to perform some calculations much faster than a clunky old classical computer. Yea you know the ones which use to use silicon, chew up a lot of power and have those crude spinning disk drives.
Yet we all know that a computer is more than its bits as you also need a “register” to hold your qubits along with performing operations on them. Thinking about it, we also will need some memory too, so that you can store our qubits between operations. Then my favorite as we will need to be able to initialize then provide a readout of qubits so that we can start and end our calculations. However this is where we hit a bit of a problem and things work better on paper then on the desk top as there are groups of researchers who have done all of these separately, not together.
The issue is our friends the Qubits don’t have a long life in the solid state as entanglement lasts a few hundred nanoseconds and coherence decays away faster than a fruit fly. Yet where there is a will there always seems to be a way, and despite these challenges, a group of researchers seem to have managed to make themselves an entire quantum microprocessor out of superconducting qubits.
While rather basic, the computer is comprised of a two-qubit register made from SQUIDs (superconducting quantum interference devices), two additional SQUIDs that can be used to zero the register acting as a readout with microwave resonator striplines, which act as memory. Yet the most interesting part is a bus that couples the two register qubits together. Via this bus, it enables the researchers to program the register to perform various logical operations which makes it something we could call a microprocessor.
Yet while all still on a laboratory bench, it does provide significant promise on delivering the holy grail of supercomputing which we desperately need to keep the likes of Moore’s Law cruising down the information super highway in style…