Quantum computing is attracting a lot of attention these days, and to understand quantum computing, you need to understand what a qubit is.
A qubit, a shortened term for quantum bit, is the fundamental unit of information in quantum computing.
Understanding qubits
Qubits differ from classical bits, which are coded as only 0 or 1. A qubit can be a combination of both 0 and 1 simultaneously. One way to think of it is as a coin spinning between a 0 and a 1 axis. Qubits are created with quantum particles, the smallest building blocks known in the physical universe.
Qubits can be made by using quantum particles like electrons, trapped ions, or photons, keeping them in motion for the qubit to be a combination of 0 and 1.
Qubits are based on the laws of quantum physics and must be able to exist in a quantum superposition, meaning a position between 0 and 1.
Because of the advantages of quantum mechanics, qubits can store more data than traditional bits, making quantum computers immensely more powerful.
Why do qubits matter
To answer why qubits matter, we have to explore the potential of quantum computers, which began to catch investors' eyes in 2025 after Google said it hit a major milestone in quantum computing in late 2024.
Through qubits and quantum technology, quantum computers are able to perform advanced computations that would take traditional computers thousands of years to accomplish.
Because they can solve highly complex problems so much faster than traditional computers, quantum computers have a lot of potential applications, enabled by qubits.
Applications of qubits/quantum computing
The market is beginning to sense the potential for disruption using quantum computing.
Potential applications include medical research, machine learning, artificial intelligence, and mitigating climate change.
Currently, quantum computers are primarily performing benchmark tasks to demonstrate their capabilities. Google, for example, is aiming to build a large-scale quantum computer that can do complex, error-corrected computations, which will pave the way for potentially breakthrough applications.
Those applications include projects that quantum computing is particularly well-suited for, like drug discovery; classical computers can't simulate drug molecules. Quantum computing may also help make chemical production safer by finding new reactions to make chemicals.
Battery technology is another way that quantum computing could help achieve a breakthrough. Electrochemical battery simulations could lead to higher-performing batteries that last longer and have more power, helping the economy move toward a renewable future.
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How qubits are used
Let's take an example of one quantum computing company to see how it makes and uses qubits.
One of the most promising pure-play quantum computing companies is IonQ. IonQ uses ionized ytterbium atoms for its qubits because of their ability to supercharge complex computations. Ytterbium is an element, so every ytterbium atom is identical to every other. They also have the ability to remain in a quantum state for a long period of time, making them ideal for quantum computing applications.
IonQ uses a trapped-ion process to make a ytterbium ion by removing one electron, leaving it with a positive electrical charge and one valence electron. It then holds the ion in a 3D space with a trap built on 100 tiny electrodes.
There are different ways to build a quantum computers, but the trapped-ion method has worked well for IonQ. As the technology develops, we're likely to see more ways of developing and building qubits and powering quantum computers.
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