How to Scale Up Quantum Computing Applications

Quantum computing attempts to leverage tremendous parallelism in computation through the investigation of several entangled quantum states at the same time, instead of individual classical states sequentially.

Challenges

Quantum computing is expected to have a wide range of applications, specifically in computational problems that are lengthy or previously unsolvable. This is especially vital for unstructured search, optimization, logistics, and materials simulation.

In the short run, quantum annealers, simulators, and the so-called Noisy Intermediate Scale Quantum (NISQ) machines — that work using qubits varying in numbers from 50 to a few hundred — are likely to be useful, as well as commercially feasible. It is yet to be ascertained whether they will exhibit quantum supremacy as a specific application functionality or general-purpose machine, in comparison with classical equivalents.

A number of leading candidate qubit contenders necessitate a low-temperature environment to operate, and to eliminate sources of noise. These on- and off-chip sources of noise lead to decoherence and higher error rates.

It is expected that fully fault-tolerant quantum computers will need a million qubits or even more, and might take a few decades to develop. Meanwhile, error avoidance and low-temperature performance are crucial to offer a usable and beneficial NISQ machine.

Oxford Instruments has the Solution

The energy-level separation of the 1s and 0s of qubits at low temperatures needed for operation are essentially in the gigahertz frequency range. Moreover, precisely shaped nanosecond pulses are needed to manipulate the computational operations.

It is very difficult to maintain the accuracy and precision of pulse shape. Therefore, it is vital to scale up engineering solutions to ensure low-impedance, low-noise amplified output lines and low-noise, wide-band attenuated input lines. The optimized cabling solutions offered by Oxford Instruments for quantum computation provide long-term reliability, low noise performance, and modularity.

Impact Through Applications

Materials Modeling

As in the case of materials simulation, protein folding, drug discovery, battery modeling, and catalysis are possible candidate problems to be overcome with the help of quantum computing. Instead of using qubits to simulate materials, modeling involves computational methods that conform to quantum computing over classical computing, to widen the array of species that can be examined for both the accuracy and speed of the computation.

Optimization

Analytical methods may not be applicable to solve various types of problems. Problems of such types are more prevalent in finance, medicine, and logistics. With an increase in the number of variables in a problem, the sequential nature of classical computing tends to fail.

A 270 variable problem already outstrips the number of atoms in the universe. The parallelism of quantum computing enables multi-variable optimization, which could have an effect on applications like cancer radiotherapy treatment, traffic flow, and flight scheduling.

Database Search

Big Data applications, ranging from the high street to CERN, demand relational database searching with structured datasets. Based on the size, unstructured datasets like text, language, and multimedia can be hard, or even impossible, to search. Quantum computing provides the options to apply optimal unstructured search methods using Grover’s Algorithm. Drug discovery and security are potential areas for development.

Security

Without quantum cryptography, quantum computers could be a threat to encryption mechanisms. RSA-2048 encryption would require several millions of years to solve using a classical computer, while it can be solved in a few days using a quantum computer that operates with 2000 qubits and gigahertz clocking speed.

In order to tackle this risk, quantum technologies are also being used to create noncomputational security protocols that will remain secure in spite of the advances in quantum computing.

Case Study — Teleportation and Quantum Communications

Within the framework of the European Quantum Flagship QMiCS program, Oxford Instruments is an important partner promoting the development of a quantum microwave local area network. This framework will facilitate quantum communication protocols like teleportation between two superconducting quantum nodes. In the future, this technology could be applied for distributed quantum computing and radar-style quantum sensing using microwaves.

This information has been sourced, reviewed and adapted from materials provided by Oxford Instruments Nanoscience.

For more information on this source, please visit Oxford Instruments Nanoscience.