In the recent past, several new computer technologies have surfaced in the world, and quantum computing is certainly one of those that can revolutionize the whole technological spectrum. Quantum computing is a computer technology that makes use of quantum theory principles. Where classical computers store information as bits with binary values 0s and 1s, quantum computers use quantum bits (or qubits) that can have more than one value at the same time (i.e. not restricted to 1 or 0 as in classical computers). Therefore, interconnected qubits can use their oscillating wave-like quantum values or states to perform calculations that may otherwise take thousands of years. Classical computers use a binary stream of electrical impulses (1 and 0) to convert and store data in bits, which limits their processing capability as compared to quantum computers.
Brief History
The idea of quantum computers was conceived by computer scientists in the 1980s. The main source of its perception was Quantum Mechanics, which was worked out in the first quarter of the 20th century and th century, and remains the foundation on which many latest technologies still depend. It elaborates that certain numerical problems could be resolved more efficiently using quantum algorithms than by using their classical equivalents. Quantum computing can analyze a large number of possibilities and select viable solutions to complex problems. Such enormous computing capability and its potentially connected market size have invited the attention of some of the leading global business organizations.
Quantum Computer vs. Classical Computer
Quantum computer has a more simple structure than classical computer. It has no memory or processor. All a quantum computer uses is a set of superconducting qubits. These two also differ in the processing of information. The processing power of quantum computers increases exponentially with the addition of more and more qubits. However, classical processors use bits (0s and 1s) to process input data. Their increase in computing power is directly proportional to increases in number of bits. Classical computers have much less computing power and they are useful for everyday tasks with low potential rates of error. Contrarily, quantum computers are suitable for heavier tasks, e.g. data analysis, executing simulations, and production of powerful and energy-efficient batteries, etc. However, they are prone to high error rates. Classical computers don’t need extraordinary care and maintenance. They use an internal fan to evade overheating. Quantum processors need protection against even small vibrations and heat and thus need to be kept at very low temperatures. Quantum computers will be capable to store much more information than classical computers, which allows them to execute complex tasks much faster than their classical counterparts.
How hard is it to build a Quantum Computer?
As per quantum theory, matter exists in a variety of possible configurations or states. Contrary to classical probability theory, these configurations of the quantum state may interfere with each other like waves in a water pool. If we want to figure out quantum evolution, we will have to trace every possible configuration in which a quantum system could exist. As a result, developing a quantum computer takes much more time and effort. Google has been working on building a quantum computer for many years and has spent billions of dollars on this project. It anticipates having its quantum computer up and running by 2029.
Cost of a Quantum Computer
Due to its complexity, sophisticated design, and fragility, it costs billions of dollars to develop a quantum computer. However, many technology companies around the world are currently striving to minimize development costs. For example, Chinese firm Shenzhen SpinQ Technology has plans to produce a $5,000 desktop quantum computer for educational institutions shortly.
Speed of a Quantum Computer
A quantum computer is much faster than even a supercomputer. Google’s quantum computer under development, Sycamore, is believed to have performed a computation in 200 seconds, as compared to the 10,000 years required by one of the world’s fastest computers, IBM’s Summit. IBM strikes down Google’s claim, saying its supercomputer needed 2.5 days for the same execution. Still, IBM’s Summit is 1,000 times slower than Google’s quantum computer.
Composition of a Quantum Computer
A quantum computer has three primary parts:
• A device that accumulates the qubits
• A method of performing quantum operations (quantum gates) on the qubits and evaluating them
• A classical computer to execute a program and send instructions
Features of Quantum Computing
Two main features of quantum physics enable quantum computers to perform computations at very higher speeds and with much less energy consumption than classical computers.
• Superposition
A qubit stores its quantum information in a state of superposition, which means a combination of all possible configurations of the qubit. The collection of qubits in superposition can create a complex, multidimensional computational environment, where complex problems can be represented and resolved in new ways.
• Entanglement
Pairs of qubits can be accumulated to get entangled. This means that two qubits then exist in the same state. In such a state, changing one qubit directly predictably affects the other. Quantum algorithms are designed to take advantage of this relationship to solve complex problems.
Limitations of Quantum Computing
Quantum computing proposes a huge development, problem-solving, and expansion potential in many technology fields and industries. However, it still has its inherent limitations.
• The quantum state can be disturbed by slight vibrations or temperature variations. This can cause qubits to fall out of superposition and cause computational errors. Therefore, qubits must be protected from such disturbance by keeping them at extremely low temperatures, insulation, and vacuum chambers.
• Error correction during the computing stage is yet to be perfected. This makes computations unreliable. Qubits can’t take advantage of conventional error correction techniques used by classical computers.
• Security and quantum cryptography are still under development.
• A shortage of qubits prevents quantum computers from their anticipated effective use.
Quantum Computing Applications
Some of the potential applications of quantum computing are:
• Cyber security
• Artificial intelligence
• Energy-efficient batteries
• Cleaner fertilization
• Electronic materials discovery
• Weather forecasting
• Drug development
• Financial modeling
• Traffic optimization
