As said in the last post (Are Quantum Technologies the future?), the quantum technologies has got a lot of attention from the media in the last decade. There are several useful applications for quantum technologies, like sensing, measurements, simulations, etc. But there’s also an application for computation.
The basic idea of Quantum Technologies is to take advantagem of the properties of quantum particles to have a better performance in whatever application you’re using. Quantum particles don’t follow the same rules as Classic Physics, and some properties can be taken advantage of for performing better measurements and procedures.
When we talk about quantum computing, we can take advantage of the Superposition state of the particles for making more than one operation by clock, so the quantum computer can perform more operations in the same quantity of bits of a classical computer. A superposition state is basically the probabilities of a bit being in the state 0 or 1. Since it’s a probabilistic (not a deterministic) approach, we can work both the possible values at the same time, what we call the positive and negative state.
But what is the state of a quantum particle? A state is the deterministic values of the properties of the particle. For example, for a photon, we can consider the polarization (the spatial propagation direction of the wave) as the possible value. If the photon is in a horizontal polarization, we can assume it as 1, and if it’s in a vertical polarization, we can consider it as 0, for example. The decoding of the quantum state to a classical bit is just a matter of convenience, you can decide whichever protocol you wish for coding and decoding.
There are a lot of other ways for defining criteria for representating Quantum Bits (qubits), like trapped ions, phonons propagation, transmons, and others. Photons are interesting for the next topic I’ll be covering, Quantum Communications.
That’s all for now, folks!
That’s just a short post for setting an introduction to anyone that didn’t had contact with quantum technologies. Next topics from this line we will be covering in more details the principles for quantum computation while talking about other applications.