What Is Quantum Computing?

Quantum computing is an area of computer science that uses the principles of quantum theory. Quantum theory explains the behavior of energy and material on the atomic and subatomic levels.

Quantum computing uses subatomic particles, such as electrons or photons. Quantum bits, or qubits, allow these particles to exist in more than one state (i.e., 1 and 0) at the same time.

Theoretically, linked qubits can “exploit the interference between their wave-like quantum states to perform calculations that might otherwise take millions of years.

Classical computers today employ a stream of electrical impulses (1 and 0) in a binary manner to encode information in bits. This restricts their processing ability, compared to quantum computing.

Uses and Benefits of Quantum Computing

Quantum computing could contribute greatly to the fields of security, finance, military affairs and intelligence, drug design and discovery, aerospace designing, utilities (nuclear fusion), polymer design, machine learning, artificial intelligence (AI), Big Data search, and digital manufacturing. 

Quantum computers could be used to improve the secure sharing of information. Or to improve radars and their ability to detect missiles and aircraft. Another area where quantum computing is expected to help is the environment and keeping water clean with chemical sensors.

Here are some potential benefits of quantum computing

• Financial institutions may be able to use quantum computing to design more effective and efficient investment portfolios for retail and institutional clients. They could focus on creating better trading simulators and improving fraud detection.
• The healthcare industry could use quantum computing to develop new drugs and genetically-targeted medical care. It could also power more advanced DNA research.
• For stronger online security, quantum computing can help design better data encryption and ways to use light signals to detect intruders in the system.
• Quantum computing can be used to design more efficient, safer aircraft and traffic planning systems

Features of Quantum Computing

Superposition and entanglement are two features of quantum physics on which quantum computing is based. They empower quantum computers to handle operations at speeds exponentially higher than conventional computers and with much less energy consumption.

Superposition

According to IBM,  it’s what a qubit can do rather than what it is that’s remarkable. A qubit places the quantum information that it contains into a state of superposition. This refers to a combination of all possible configurations of the qubit. “Groups of qubits in superposition can create complex, multidimensional computational spaces. Complex problems can be represented in new ways in these spaces.

Entanglement

Entanglement is integral to quantum computing power. Pairs of qubits can be made to become entangled. This means that the two qubits then exist in a single state. In such a state, changing one qubit directly affects the other in a manner that’s predictable.

Quantum algorithms are designed to take advantage of this relationship to solve complex problems. While doubling the number of bits in a classical computer doubles its processing power, adding qubits results in an exponential upswing in computing power and ability.

Decoherence

Decoherence occurs when the quantum behavior of qubits decays. The quantum state can be disturbed instantly by vibrations or temperature changes. This can cause qubits to fall out of superposition and cause errors to appear in computing. It’s important that qubits be protected from such interference by, for instance, supercooled refrigerators, insulation, and vacuum chambers.

Limitations of Quantum Computing

Quantum computing offers enormous potential for development and problem-solving in many industries. However, currently, it has its limitations.

• Decoherence, or decay, can be caused by the slightest disturbance in the qubit environment. This results in the collapse of computations or errors to them. As noted above, a quantum computer must be protected from all external interference during the computing stage.
• Error correction during the computing stage hasn’t been perfected. That makes computations potentially unreliable. Since qubits aren’t digital bits of data, they can’t benefit from conventional error correction solutions used by classical computers.
• Retrieving computational results can corrupt the data. Developments such as a particular database search algorithm that ensures that the act of measurement will cause the quantum state to decohere into the correct answer hold promise.8
• Security and quantum cryptography are not yet fully developed.
• A lack of qubits prevents quantum computers from living up to their potential for impactful use. Researchers have yet to produce more than 128.7

According to global energy leader Iberdola, “quantum computers must have almost no atmospheric pressure, an ambient temperature close to absolute zero (-273°C) and insulation from the earth’s magnetic field to prevent the atoms from moving, colliding with each other, or interacting with the environment.”

“In addition, these systems only operate for very short intervals of time, so the information becomes damaged and cannot be stored, making it even more difficult to recover the data.