Abstract—This research suggests that quantum computing brings together ideas from classical information theory, computer science, and quantum physics. This modern way of computing is based on the science of quantum mechanics and its unbelievable phenomena. It Theoretically has computing power that is many orders of magnitude greater than that of conventional computers.

Keywords—entanglement, a quantum bit (qubit), quantum logic gates, decoherence, superposition

I.Introduction

Quantum computing is one of the hottest topics in the technology sector today. The technology enables individuals and companies to solve computational problems previously considered intractable. Cryptography, chemistry, quantum simulation, optimization, machine learning, and numerous other fields have been significantly impacted by this technology. While quantum computers aren’t going to replace classical immediately, quantum technology is significantly changing the way the world operates. Quantum computing is generally viewed as a field of study centered on developing computer technology based on the principles of quantum theory. This area of physics explains how matter and energy behave at the atomic and subatomic levels.

1.1  Existing system  

Classical computing is another name for binary computing. In this traditional approach to computing, information is stored in bits that are represented logically by either a 0 (off) or a 1 (on). Today's processors, including x86 and ARM Processor, support classical computing.

1.2Motivation

Quantum computers can solve what computer science calls "NP-complete" problems, the problems that are impossible or nearly impossible to calculate on a classical computer.
The trick in quantum computing is to harness the entanglement of different particles -- what Einstein called the "spooky action at a distance" -- that allows one particle to affect another somewhere else.

II.System Overview

The Quantum Computer is programmed by changing the magnetic conditions around quantum bits, or "qubits," creating relationships between them that model the physical embodiment of the equation the programmer is trying to solve. The results are read by detecting the direction of the current within the qubit when the calculations are complete.

Qubits are prone to errors. All sorts of environmental factors like thermal fluctuations, electromagnetic radiation, and magnetic fields can knock a qubit out of its intended state. That degradation of information is known as decoherence and can occur in a fraction of a second. Despite the use of refrigeration to reduce thermal fluctuations, decoherence eventually creeps in and produces hardware errors, like accidentally flipping a qubit’s state from 0 to 1.

1.1 Logic-level compilation

A quantum circuit is a map of sequential logic gates that are applied to a series of qubits to run an algorithm. A simple example of a circuit that two qubits in a Bell state are shown


Two qubits start in pure 0 states. A Hadamard gate acts on the first qubit and puts it in a superposition of states 0 and 1 with an equal probability of finding the qubit in each state. The two-qubit CNOT gate flips the target qubit (⊕) to 1 only if the control qubit (•) is in state 1, thereby producing the entangled output state shown.

1.2    Quantum algorithms and applications

Quantum algorithms play the same role as classical algorithms: They provide step-by-step instructions for completing a computational task.
Although a regular algorithm could in principle be run on a quantum computer, a true quantum algorithm takes advantage of the underlying hardware’s quantum nature. For example, manipulating one qubit in a quantum computer affects the entire n-qubit state and each of the 2ⁿ coefficients needed to describe it, effectively doing that many operations in parallel. However, it’s not quite parallel computing. When the final qubit states are measured, each is either a 0 or a 1; the algorithm outputs only n values rather than all 2ⁿ coefficients.
Quantum Fourier transforms are also significantly faster than their classical counterparts. Other tasks, such as playing chess, garner little to no benefit from quantum algorithms because the number of steps needed would still grow too quickly with the complexity of the problem.
A variational quantum algorithm is a compromise between classical and quantum ones. It breaks up a computation into a small quantum component and a larger classical optimization problem and therefore requires a much smaller quantum computer than, say, the quantum Fourier transform. Such algorithms are promising for solving problems in finance, logistics, and chemistry.

III. User Interface, QAAS, and Operating System

Most people who want to use quantum computers aren’t going to build or even buy one—at least not anytime soon. To facilitate access to the limited existing quantum computing resources, companies have put together cloud-based infrastructures that allow remote operation. As in a classical computer, the highest level of the quantum computing stack provides the interface that users interact with.
Amazon Braket, Microsoft Azure Quantum, and Rigetti Quantum Cloud Services are examples of quantum-as-a-service (QAAS) offerings. However, those companies aren’t necessarily providing access to their own quantum computers; rather, they connect users and computers. For example, Amazon Braket can connect users to resources from D-Wave, Rigetti, and IonQ. That approach makes quantum computers similar to other managed, cloud-based computational resources, such as graphical processing units.

The above services can be used to write code using high-level programming languages. The resulting algorithms probably wouldn’t look particularly exotic to someone with programming experience. For example, the open-source software development kits Ocean (from D-Wave), Qiskit (from IBM), and Forest (from Rigetti) support the programming language Python. Languages specifically designed for quantum computing include Quantum Computation Language (QCL), which resembles C, and Q Language, which works as an extension of C++. The code defines a sequence of operations that constitute a logical algorithm.


A short Qiskit algorithm, akin to a “Hello, World!” program, initializes one qubit in state 1.

IV. Acknowledgement

We sincerely thank the faculty of the Electronics and Communication Engineering Dept. at Anil Neerukonda Institute of Technology and Sciences for giving me the chance to write this paper. Without their active involvement and the right guidance, this would not have been possible.

V. References

Shankar Nambala
Dept. of Electronics and Communication Engineering
Anil Neerukonda Institute of Technology & Sciences
Visakhapatnam, India
nssaiumashankar.20.ece@anits.edu.in

Note: Opinions expressed by authors are their own.