Quantum computing: exploring its rise and the challenges ahead

The quantum computing market is growing as countries increase their funding into this revolutionary technology in a bid to be a global leader in the field. In the UK, the National Quantum Strategy is a 10-year vision for the UK to be a leading quantum-enabled economy.

According to McKinsey, the potential quantum technology market size globally could be up to $173billion by 2040.

This blog outlines what the differences between classical and quantum computing are, the potential applications of this technology, and the main challenges of quantum computing.

What is quantum computing?

Quantum computing uses specialised technology, such as computer hardware and algorithms using the principles of quantum mechanics, to solve complex problems quicker than classical computers. It has more computational power than classical computers due to these advancements.

It is a multidisciplinary field comprising computer science, physics, and mathematics.

What are the differences between classical and quantum computing? 

Classical computers use bits to process information and operate on binary states of 0s and 1s. Quantum computers use quantum bits, or qubits, which can exist in superposition states of 0, 1, or both simultaneously. This superposition property, combined with the property of quantum entanglement, enables quantum systems to perform complex calculations at unprecedented speeds.

While classical computers are effective for a wide range of tasks, particularly day-to-day personal and professional tasks, they struggle with problems involving large datasets, complex optimisation, and factorisation of large numbers. Quantum computers harness quantum mechanics to solve these problems more efficiently, making them much quicker than classical approaches.

What are the potential applications of quantum computing?

Quantum computing has the potential to be transformative to society across many industries. There are some applications which look particularly promising, which are detailed below.

Drug discovery

Quantum computing has the potential to dramatically speed up the process of developing new drugs by improving target identification, drug design and toxicity testing, making pharmaceutical research and development less reliant on trial and error.

Healthcare

As well as drug discovery, quantum computing can have a positive impact on other areas of healthcare. It can help to transform the industry by offering diagnostic assistance - diagnosing patients quicker and more accurately, by personalising interventions and treatments, and by optimising insurance premiums and pricing to make healthcare more globally accessible to all.

Cybersecurity and cryptography

Cybersecurity tools used widely on classical computers won’t be secure against mature quantum technology, making it easier for hackers to bypass RSA cryptography. Quantum Key Distribution (QKD) is an ultra-secure network which responds to the quantum threat faced by businesses.

Financial modelling

Having more computational speed is a big advantage in the financial sector as simulating market predictions and risk management is improved by being able to do them more quickly. 

Material science

Quantum computing applications can be used in this space to manipulate molecules and material behaviour to discover new uses. Quantum mechanics is used to create the motion and interaction of subatomic particles. IBM’s Institute for Business Value explores how quantum computing can accelerate the development of new methods and materials in the chemicals and petroleum sectors.

Artificial intelligence and machine learning

Using quantum algorithms within conventional machine learning pipelines can increase the speed of complex calculations, as they are quicker than typical machine learning algorithms. There is potential for quantum machine learning and AI across various industries, for tasks such as autonomous driving, automated trading, and predictive maintenance.

Supply chain

There is the opportunity to apply the power of quantum computing to improve supply chains worldwide. Using the quantum advantage, supply chain operations can be modelled more quickly and efficiently, enabling businesses to manage the enormous complexity of existing supply chains better.

What are the main challenges with quantum computing?

Despite its potential, quantum computing still faces significant challenges. Some of these include:

• Error correction: Developing effective error correction methods is essential to mitigate decoherence and ensure reliable quantum computations.

• Scalability: Building scalable quantum hardware with a large number of stable qubits is a major hurdle. Current quantum computers from companies such as IBM and Microsoft are still limited in their computational capabilities.

• Quantum programming: Creating robust quantum programming languages and frameworks that can effectively harness quantum algorithms is crucial for the development of quantum applications.

• Quantum supremacy: Achieving quantum supremacy, where quantum computers can solve problems that classical supercomputers can’t, is a key milestone which requires further breakthroughs in quantum research.

• Connectivity and ecosystem: Building a robust quantum ecosystem with strong connectivity between quantum systems and classical systems is necessary for real-world applications.

What are the current limitations of quantum computing technology?

As quantum technologies are in their relative early stages there are still some limitations with them. Multiple different startups and research centres are working on producing a fault-tolerant quantum computer. These are some of the kinks to be worked out before quantum computing hits its full potential:

• High fidelity: A defining hurdle of quantum computing is the need to increase qubit count and complex algorithms while maintaining high levels of qubit quality.

• Computation speed: Individual qubits can retain their quantum state (coherence) for only a limited time, so complex computations should be done as quickly as possible, before qubits lose coherence.

• Cooling and environmental control: The required scale of cooling equipment in terms of size and power for quantum technologies is currently beyond available equipment.

• Manufacturing: Some quantum designs and components require new manufacturing techniques, creating a need for new automated manufacturing and testing at scale.

Learn more about the potential of quantum computing

Quantum computing is still a new industry and has a huge amount of potential to grow as new discoveries are constantly being unearthed. The need for qualified individuals with an understanding of this exciting field is essential, and the industry is expanding rapidly in the UK and the European Union - indeed, scientists from EU institutions contributed most often to quantum information publications in 2023.

Take the first step towards the field of quantum computing by studying with City, University of London. We have a suite of computer science master’s degrees available to be studied online and part-time, enabling you to expand your professional development whilst continuing to earn, fitting your degree around your current commitments.