In the firstarticlewe brushed on quantum computing basics, in this edition we will explore types of qubits.
Quantum computers use units called qubits, formally known as quantum bits. The qubits differ from normal bits as they have the ability to take on two values.
It all starts with entangling the qubits, there are multiple ways to perform the process of entanglement, which will form the basis of our article.
Types of Qubits
Used by Tech giants Google and IBM, these are the most advanced type of qubits.
The qubits are placed inside microchips and cooled to about 20 millikelvins to reach superconducting state. The problem with this approach is quantum decoherence, where the qubits disappear usually after 10 microseconds.
We need to keep the system in a quantum state to perform a certain computational task, 10 microseconds tends to be very challenging.
Photonic Quantum Computing
Photons can be operated at room temperature with quantum effects that are long-lasting. As you may recall with the superconducting process we need extremely low temperatures and face a challenge with a short-lived quantum effect.
In this approach the qubits are properties of photons, they may lie within a photon itself or a certain state of a photon. These systems get really huge with one reported to cover an entire table. Compare these large objects to a tiny chip used for superconductor technology.
Also referred to as trapped ion quantum technology, with this technique qubits with missing electrons are trapped inside electromagnetic fields. They are moved around using a laser.
This will begin the entanglement process, they are similar in size to the superconducting qubit chip with a less extreme temperature.
As much as this method may seem ideal, we need to consider the slow reaction rate, this gives the superconducting qubits an edge over them.
Topological Quantum Computing
Not yet demonstrated by any institution, we store data in quasiparticles making the data vigorous to decoherence. Described by Microsoft as “upside is enormous and there is practically no downside”.
After a few years of making such a bold statement, Microsoft had to retract its paper demonstrating quasi-particles that they used.