Quantum Computing Advantages And Disadvantages



What is quantum computing?

Quantum computing is a rapidly-emerging technology that harnesses the laws of quantum mechanics to solve problems too complex for classical computers.

Today,  Quantum makes real quantum hardware — a tool scientists only began to imagine three decades ago — available to thousands of developers.  engineers deliver ever-more-powerful superconducting quantum processors at regular intervals, building toward the quantum computing speed and capacity necessary to change the world.

These machines are very different from the classical computers that have been around for more than half a century. Here’s a primer on this transformative technology.


Quantum computers have good parallelism, fast information processing speed, large amount of information storage, and performance in many fields far surpasses classical computers.

Quantum computing uses the qubit as the basic unit of information rather than the conventional bit. The main characteristic of this alternative system is that it permits the coherent superposition of ones and zeros, the digits of the binary system around which all computing revolves.

Quantum Computer vs. Classical Computer

Quantum computers process information differently. Classical computers use transistors, which are either 1 or 0. Quantum computers use qubits, which can be 1 or 0 at the same time. The number of qubits linked together increases the quantum computing power exponentially. Meanwhile, linking together more transistors only increases power linearly.

Classical computers are best for everyday tasks that need to be completed by a computer. Meanwhile, quantum computers are great for running simulations and data analyses, such as for chemical or drug trials. These computers must be kept ultra-cold, however. They are also much more expensive and difficult to build.

Classical computing advances include adding memory to speed up computers. Meanwhile, quantum computers help solve more complicated problems. While quantum computers might not run Microsoft Word better or faster, they can run complex problems faster.

For example, Google’s quantum computer that’s in development could help with many processes, such as speed up machine-learning training or help create more energy-efficient batteries.

Quantum computing has a number of other applications, including securely sharing information. Other methods include fighting cancer and various health concerns, such as cancer and developing new drugs. As well, quantum computers can help improve radars and their ability to detect such things as missiles and aircraft. Other areas include the environment and using quantum computing to keep the water clean with chemical sensors

Google, in 2019, proved that a quantum computer can solve a problem in minutes, while it would take a classical computer 10,000 years.

How do quantum computers work?

Quantum computers are elegant machines, smaller and requiring less energy than supercomputers. An IBM Quantum processor is a wafer not much bigger than the one found in a laptop. And a quantum hardware system is about the size of a car, made up mostly of cooling systems to keep the superconducting processor at its ultra-cold operational temperature.

A classical processor uses bits to perform its operations. A quantum computer uses qubits (CUE-bits) to run multidimensional quantum algorithms.

Your desktop computer likely uses a fan to get cold enough to work. Our quantum processors need to be very cold – about a hundredth of a degree above absolute zero. To achieve this, we use super-cooled superfluids to create superconductors.

At those ultra-low temperatures certain materials in our processors exhibit another important quantum mechanical effect: electrons move through them without resistance. This makes them “superconductors.” When electrons pass through superconductors they match up, forming “Cooper pairs.” These pairs can carry a charge across barriers, or insulators, through a process known as quantum tunneling. Two superconductors placed on either side of an insulator form a Josephson junction.

Our quantum computers use Josephson junctions as superconducting qubits. By firing microwave photons at these qubits, we can control their behavior and get them to hold, change, and read out individual units of quantum information.

A qubit itself isn’t very useful. But it can perform an important trick: placing the quantum information it holds into a state of superposition, which represents 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 is a quantum mechanical effect that correlates the behavior of two separate things. When two qubits are entangled, changes to one qubit directly impact the other. Quantum algorithms leverage those relationships to find solutions to complex problems.

Why do we need quantum computers?

For some problems, supercomputers aren’t that super.

When scientists and engineers encounter difficult problems, they turn to supercomputers. These are very large classical computers, often with thousands of classical CPU and GPU cores. However, even supercomputers struggle to solve certain kinds of problems.

If a supercomputer gets stumped, that’s probably because the big classical machine was asked to solve a problem with a high degree of complexity. When classical computers fail, it’s often due to complexity

Complex problems are problems with lots of variables interacting in complicated ways. Modeling the behavior of individual atoms in a molecule is a complex problem, because of all the different electrons interacting with one another. Sorting out the ideal routes for a few hundred tankers in a global shipping network is complex too.

Quantum computing advantages and disadvantages

Quantum computing is an ordinary computer chip that uses bits. These look like a tiny switch, that can either be in the off position represented by a zero or in the on position represented by a one. Every application you can use and the website you visit and also photograph you take is ultimately made up of millions of these bits in some combination of ones and zeroes. Let us discuss the advantages and disadvantages of quantum computing to better understand this topic.

Advantages of Quantum computing:

  1. The main advantage of quantum computing is that it is even classical algorithm calculations. They are also performed easily which is similar to the classical computer.
  2. If we adding the qubits to the register we increase its storage capacity exponentially.
  3. In this computing qubit is the conventional superposition state. So there are advantages of exponential speedup to the resulted by handle the number of calculations and method.
  4. Quantum computing required less power.
  5. The other advantage of quantum computing is it can execute any task very faster and very accurately compared to a classical computer. Generally, the atom changes very faster in the case of traditional computing whereas in quantum computing it changes even faster.

Disadvantages of Quantum computing:

  1. The research for this problem is still continuing the effort applied to identify a solution for this problem that has no positive progress.
  2. Qubits are not digital bits of the day thus they cannot use as conventional error correction.
  3. The main disadvantage of Quantum computing is the technology required to implement a quantum computer is not available at present days.
  4. The minimum energy requirement for quantum logical operations is five times that of classical computers.
  5. Quantum CPU will have efficiency and heating problems of its own.
  6. When a measurement of any type is made to a quantum system, decoherence is totally broken down and the wave function collapses into a single state.

Drop your comment

Related Post

Leave a Reply

Your email address will not be published.