How quantum technology applications enable precision for the unknown.

After more than 100 years of research, quantum technology is increasingly finding its way into everyday life. Examples include its use in cell phones, computers, medical imaging methods and automotive navigation systems. But that’s just the beginning. Over the next few years, investment will increase significantly and lots of other applications will take the world by storm. While test & measurement equipment from Rohde & Schwarz and Zurich Instruments is helping develop these applications, the technology group’s encryption solutions are ensuring more secure communications based on quantum principles.

Expectations for quantum technology are greater than in almost any other field. That’s no surprise, given the financial implications associated with the technology. For example, consulting firm McKinsey & Company estimates the global quantum technology market could be worth 97 billion dollars by 2035. According to McKinsey, quantum computing alone could be worth 72 billion dollars and quantum communications up to 15 billion.

Previous developments clearly show that the projected values are entirely realistic. Many quantum effects have become part of our everyday lives. Modern smartphones, for example, contain several hundreds of billions of transistors, predominantly in flash memory chips. Their function – controlling currents and voltages – is based on the quantum mechanical properties of semiconductors. Even the GPS signals used in navigation systems and the LEDs used in smartphone flashlights are based on findings from quantum research.

To celebrate these achievements, UNESCO declared 2025 the “International Year of Quantum Science and Technology” – exactly 100 years after German physicist Werner Heisenberg developed his quantum mechanics theory based on the research findings of the time. Quantum technology was also in the spotlight with the 2025 Nobel Prize in Physics, which was awarded to quantum researchers John Clarke, Michel Devoret and John Martinis.

Fast. Faster. Quantum computing.

Our world is controlled by binary code. Conventional computers process data as sequences of ones and zeros, true or false, off or on. This applies to everything, from simple text processing to virtual reality in the metaverse. But the world we live and work in is becoming increasingly complex. The amount of data we need to process is growing rapidly. In 2024, global digital data traffic had more than quadrupled over the space of just five years to 173.4 zettabytes. By 2029, experts believe this number will reach 527.5 zettabytes, equivalent to 527.5 trillion gigabytes.

Conventional computers face two insurmountable obstacles as a result: time and complexity. The larger the volume of data, the more time you need to process that data sequentially. The more complex the problem, the lower the probability that binary code, with only two states, will be able to efficiently calculate a solution. Quantum computers have the potential to overcome both obstacles using insights from modern physics.

Hand in hand instead of either-or

Like conventional bits, quantum bits (qubits) form quantum mechanical memory units. In addition to just zeros and ones, they can also assume overlapping, mixed states. This simultaneity represents a fundamental technological paradigm shift. We can now run conventional sequential calculation methods simultaneously, which is why a quantum computer can save so much time.

But above all, the new quantum mechanical approach allows us to process new and much more complex questions. However, it’s not an either-or decision, either conventional processing power or quantum computing. Instead, what matters is integrating existing and quantum systems depending on the task.

Physics versus logic

In the quantum world, a particle can be in two places at the same time. Only when it is observed can you narrow down its location, for example by measuring it. This unusual property is also why it is extremely unstable. Instead of using individual physical qubits, which can be very error-prone, multiple qubits are grouped into a logical qubit. However, the challenge here is that you need quantum systems with as many as one million logical qubits in order to answer practical questions, like protein folding. A logical qubit can contain up to 100 physical qubits, but the highest processing capacity is currently only 1,225 physical qubits.

Zurich Instruments has been part of the Rohde & Schwarz family since 2021. The T&M market for quantum computing holds enormous potential for both companies. Operating and maintaining quantum computers requires a wide range of specific T&M solutions because RF signals need to be generated and measured with extremely high precision to effectively create and record quantum states. Control systems for quantum computers are part of the company’s portfolio.

Secure. More secure. Quantum communications

Quantum computers have the potential to push the limits of processing efficiency. But this brings challenges, including secure communications – increasingly a priority in view of “Q-Day”, the point at which quantum computers will be able to crack classic encryption.

That is why alternative encryption methods are becoming increasingly important. There are essentially two main approaches. The first is post-quantum cryptography, which involves conventional encryption methods with one key difference: they can survive attacks from quantum computers unscathed. The algorithms used in this approach are based on theoretical assumptions for which no effective attacks are currently known using either quantum or conventional computers.

The other approach relates to quantum key distribution (QKD). The German Federal Office for Information Security (BSI) and the National Institute of Standards and Technology (NIST) are two of the main drivers of innovation in this area. In an increasingly digitalized world, private-sector customers, and government customers in particular, are dependent on trustworthy IT security solutions. Secure communications networks have become critical infrastructure in advanced information societies.

These innovative solutions are shifting the focus of cryptology. Conventional methods, as well as more recent post-quantum methods, are based on mathematical assumptions, i.e. the idea that certain tasks cannot be calculated with sufficient efficiency. Quantum key distribution, by contrast, is based on physical principles. Rohde & Schwarz Cybersecurity is providing and leveraging its extensive expertise in security solutions, as well as its experience in building and implementing secure devices and systems, in a variety of research projects.

Innovation through collaboration

Aside from actually developing the technology, interacting with customers and participating in research groups and industry associations is also important. Rohde & Schwarz has therefore been part of many emerging networks from the very beginning. Here are just a few: