A single qubit can only accomplish so much.
- Only the entanglement of numerous qubits in quantum registers allows for the high-level parallelization of operations that make quantum computers so powerful.
- It's as if a slew of chocolate manufacturers opened their doors at the same moment.
- You can process multiple states in parallel if you have more qubits.
- Unlike traditional computers, which rise in processing power linearly as the number of computational components rises, the processing power of a quantum computer grows exponentially with the number of qubits employed.
- When 100 extra qubits are added to 100 qubits, the performance of a quantum computer does not double.
- When just a single qubit is added to the 100 qubits, it is already doubled in concept.
- In theory, adding 10 qubits to a quantum computer increases its performance by a factor of 1000, but in practice, other factors limit the increase (see below).
- With 20 new qubits, the quantum computer is already a million times faster, and with 50 new qubits, the quantum computer is a million billion times faster.
- And, with 100 additional information carriers, the performance of a quantum computer can no longer be described in numbers, even if the performance of a normal computer has only doubled.
Quantum computers, even those with just a few hundred qubits, have considerably more computing capacity than conventional computers.
- At this point, it's worth noting that entangled states' huge parallelization isn't precisely equivalent to the way parallel assembly lines function in chocolate factories.
- The way information is stored and processed in entangled quantum systems is fundamentally different from how information is stored and processed in typical digital computers.
Quantum computers do not function in parallel in the traditional sense; instead, they arrange information such that it is dispersed over many entangled components of the system as a whole, and then process it in a strangely parallel manner.
This is shown in the following example.
For a standard 100-page book, the reader gains 1% of the book's material with each page read. After reading all of the pages, the reader understands all there is to know about the book.
Things are different in a hypothetical quantum book where the pages are entangled.
The reader sees just random nonsense while looking at the pages one by one, and after reading all of the pages one by one, he or she still knows very nothing about the book's content.
Anyone interested in learning more about it should look at all of its pages at the same time.
This is because the information in a quantum book is nearly entirely contained in the correlations between the pages, rather than on the individual pages.
For the time being, the notion of qubits and quantum computers is primarily theoretical.
However, quantum engineers have made significant progress in recent years in their efforts to make quantum computers operate in reality.
Qubits may be built in a variety of ways, and they may be entangled in a variety of ways.
In theory, the goal is to use ingenious tactics to catch individual quantum systems, such as atoms or electrons, entangle them, and control them appropriately:
• One approach is to use electric and magnetic fields to fixate ions (electrically charged atoms) and then let them oscillate in a controlled manner, linking them together as qubits.
• Another approach uses atomic spin coupling, which is aligned by external magnetic fields in the same way as nuclear magnetic resonance technologies.
- The use of so-called quantum dots may also be used to manufacture qubits.
- These are regions of a material where electron mobility is highly restricted in all directions.
- This implies that energy can no longer be released continuously, but only in discrete numbers, according to quantum physics principles.
- Like a result, these points act as massive artificial atoms.
• Other researchers are attempting to build quantum computers by pumping electrons into loops in circular superconductors (known as superconducting quantum interference devices or SQUIDs), which are then disrupted by extremely thin layers of insulator.
- Companies like Google, Microsoft, IBM, and Intel have a specific emphasis on this area.
- The study takes use of the Josephson phenomenon, which states that the superconductor's Cooper electron pairs may tunnel through the insulator barrier.
- They may be in two distinct quantum states at the same time, flowing both clockwise and anticlockwise. Superpositions like this may be employed as qubits and entangled.
• Qubits might potentially be made out of certain chemical substances. A complex of a vanadium ion contained by organic sulfur compounds serves as an example. The ion's spin is so thoroughly shielded by the shell that its state (and any entanglements) are kept for a long period.
• The so-called topological quantum computer is currently a completely theoretical idea. Its origins are in mathematics, and it is still unclear whether or not it can be physically realized. It is based on what are known as anyons (not to be confused with the anions from aqueous solutions). Particle attributes may be seen in these states in two-dimensional space. As a result, they're also known as "quasi-particles." At insulator interfaces, for example, anyons may form.
Topological qubits should build highly stable networks that are significantly more resistant to perturbations than qubits in other notions.
A quantum computer is being developed by a number of research organizations throughout the globe. The tension is building! Which strategy will win out?
~ Jai Krishna Ponnappan
You may also want to read more about Quantum Computing here.
