The post Presenting the potential of quantum computing at Microsoft Ignite 2018 appeared first on Microsoft Azure Quantum Blog.

]]>Microsoft researcher Michael Beverland dangled that possibility during a presentation at Microsoft Ignite 2018 called "Explore how to develop quantum computing applications without a Ph.D.," which he co-hosted with Microsoft Quantum software design engineer Bettina Heim. The session was part of our effort to acquaint new and aspiring quantum developers with tools they can use today to learn and explore quantum computing.

The quantum computer Beverland discussed would run 250 qubits (quantum bits). Because qubits amplify their power by interweaving with one another, that will lead to a computer exponentially more powerful than anything available today. Such a computer, or even one with far fewer qubits, will crack the code of incredibly complex chemical molecules, solve medical challenges, and lead to the manufacture of "lossless" power lines.

Beverland also discussed the Microsoft approach to creating a quantum computer. Our plan is to build a full-stack quantum system, scalable to meet real-world needs. Microsoft teams today are working on all the tools needed for quantum computing:

- Quantum Development Kit.
- Algorithms and applications.
- Cryogenic controls to create the incredibly cold temperatures a quantum computer will need.
- Topological qubits scalable and stable quantum bits.

So what can we learn from the history of classical computing as we build a quantum computer? Beverland showed participants a photograph of ENIAC, one of the earliest electronic general-purposed computers. Built in 1945 at a cost of nearly $500,000, ENIAC could perform in 30 seconds certain tasks a human would require 20 hours to complete. Pointing at the people in the black-and-white photo programmers Glen Beck and Betty Snyder Beverland said: "I like to think that they could already sense that these machines, and others like them, would change the world. "In quantum computing we have a similar feeling. We think we're on the precipice of a huge change that quantum computing will bring about."

Watch a video of the presentation here:

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This site uses cookies for analytics, personalized content and ads. By continuing to browse this site, you agree to this use.In a second session, "An Introduction Quantum programming through the Quantum Development Kit and Q# Katas," Bettina Heim showed developers how to use the Microsoft Quantum Katas, an open-source project containing a series of programming exercises that provide immediate feedback as one learns how to code in Q#. "Quantum computing is going to be much the same as classical computing, and will be expressed in similar terms," Heim told her audience. "So you don't need all the details and physics formulas you can use the building blocks that we provide, and you just write algorithms."

Heim then walked participants through a half-dozen programming tests, each time running the algorithm to show that it was "solved' using quantum tools. Watch the session here:

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This site uses cookies for analytics, personalized content and ads. By continuing to browse this site, you agree to this use.As we noted in an earlier blog, it has been a year since Microsoft unveiled its vision for building a scalable quantum computer. The company is advancing toward that goal, with seven Microsoft quantum labs around the world actively engaged in engineering a topological quantum computer that scales to meet real-world computing challenges. We're forming partnerships with institutions such as the Pacific Northwest National Laboratory (PNNL), and Case Western Reserve University (CWRU) to apply quantum principles that advance science and help people. And we're offering industry-leading developer support in the form of the Microsoft Quantum Development Kit. We're making real progress on creating a quantum computer and were delighted to have the chance to share our work at Ignite 2018.

*Audience questions, and answers offered by Beverland and Heim, have been edited to add context.*

**Question: What is the status of quantum computing? How close are we to using quantum computing to solve for RSA encryption?**

**Answer:** There are various sizes of problems we might take on with quantum computers, and RSA is one of the largest. You will need a very powerful quantum computer to crack RSA for 2,000 characters. How close are we to that point? Across the world there are lots of approaches to building qubits, with all the teams working on them trying to scale up. Our approach is to build a system that scales from the outset and has much lower noise. But we are not at the stage where we have a large number of qubits. Some teams have qubits in the tens and hundreds, but they're very noisy.

**Question: My understanding is that once you read the value of qubits, they're destroyed. So how do you know when a quantum computer has solved a problem?**

**Answer:** The way that a quantum algorithm typically works is that you start the entire set of qubits in some very specific quantum state. That will be close to what we see in the classical state, with zeroes and ones. Quantum algorithms will start with all qubits being in, say, a zero state. It's an art to develop a quantum algorithm that ensures that just before you measure the state of the qubits, you're in or close to one of these classical states, so you don't get highly random answers.

**Question: Are there some kinds of problems that could be solved with a classical computer but not with a quantum computer?**

**Answer:** Theoretically, no: A quantum computer can do everything a classical computer of the same size can do. However, we have very large classical computers (petabytes) and it will be a long time before we have quantum computers with "peta-qubits." So there will be some problems for which quantum computers are theoretically as good as classical computers, but not much better, and we will presumably use classical computers to solve them simply because large classical computers will be cheaper. There are of course some high-value problems which we simply cannot solve on any classical computer in existence but which we can solve on small quantum computers. Those are the application areas we are most interested in.

**Question: Does the Microsoft Quantum Development Kit come with error detection and resolution?**

**Answer:** By design, if you're running on something like a quantum simulator, it runs perfectly. Quantum algorithms are probabilistic so there is a certain amount of error because your algorithm is not designed to be fully deterministic. And there are potential hardware errors, which depends on the hardware. Even our knowledge of how these errors are supposed to behave is a tricky thing.

**Question: There are a lot of sessions on AI (here at Ignite). Will quantum computing be more apt at building real artificial intelligence?**

**Answer:** At the minute that's unknown. It's an active area of research. A quantum computer is fundamentally a different tool, so it could open new opportunities in AI.

**Question: A qubit is a unit of storage. That also means we're going to have problems with storing that and some way to process it. Are those the next steps?**

**Answer:** We are thinking about what it takes to make a quantum application work end to end. There are practical considerations, like where does my memory go? If I want to load something then do something with it and then put it back, where does it go? Quantum computing is a little different in a lot of ways. You can have scratch space that simultaneously holds part of the memory for a computation that can be used for another computation without destroying the information it holds for the first part. Until we have the hardware to see if it works in reality, we won't know.

Want to learn more?

- Download the Microsoft Quantum Development Kit
- Follow along on the path to scalable quantum computing with the Microsoft Quantum newsletter

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]]>Reporting to Krogstrup is a team of skilled mechanical engineers, materials scientists, and quantum physicists. Together, they're synthesizing ultra-clean quantum crystals, the building blocks of future quantum computers. The Copenhagen lab will supply these crystals to Microsoft Quantum labs located in Delft, the Netherlands; Sydney, Australia; Santa Barbara, California; and other locations.

It's fitting that Copenhagen should host this groundbreaking new lab. After all, it was Danish physicist Hans Christian Oersted who in 1820 discovered the link between electricity and magnetisma breakthrough that in time helped lead to the use of electricity to run our world. Another Danish scientist, Niels Bohr, received a Nobel prize in physics in 1922 for his work on quantum theory. Bohr later founded the Institute of Theoretical Physics in Copenhagen. Our new quantum lab will lead to discoveries that are equally groundbreaking.

Given that people such as Oersted and Bohr are household names in Denmarkwith streets and parks named for themit wasn't surprising that the opening of our new lab was a newsworthy event. Danish Minister of Higher Education and Science Tommy Ahlers was among those attending, and later joked on Twitter about a TV interview he gave: "Everything was going fine until they asked me to explain the physics behind quantum computing!"

Beyond research and development, another role for the new Copenhagen lab is to help educate the public on the field of quantum computing. It's been designed such that passersby, families with children, students, and others can see researchers at work behind large glass windows creating materials that will make scalable quantum computing possible. The lab's neighbor is the Technical University of Denmark, where half of Denmark's engineers are trained. Students there are finding inspiration in the Microsoft lab and charting their own futures around quantum computing.

The Microsoft Quantum Materials Lab's impressive array of scientific equipment speaks to the exciting research it's tackling. One of the problems researchers there will investigate is how to create quantum states that are more easily interpreted. "Quantum states are extremely fragile and therefore very difficult to maintain and read," lab director Krogstrup says. "And quantum materials must be perfect. That means not one atom can lie in the wrong placeliterally. This is among the things we need to do more research in."

Quantum computing is a complex concept and can be a challenge for people to wrap their heads around. But the potential of the field is clearcreating computers far more powerful than anything available today, with the ability to solve some of the most difficult computing problems imaginable. We look forward to delivering that reality with the Quantum Materials Lab.

**Updated October 19th, 2018: **Check out this video of the grand opening of the Microsoft Quantum Materials Lab:

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This site uses cookies for analytics, personalized content and ads. By continuing to browse this site, you agree to this use.- Read this blog post to learn more about how Microsoft is Fabricating materials for a quantum computer.
- To follow along on our journey toward bringing scalable quantum computing to the world, sign up for the Microsoft Quantum newsletter.

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]]>The post Microsoft advances quantum computing vision and helps tackle real-world challenges appeared first on Microsoft Azure Quantum Blog.

]]>Later this year, we will release an update to the Microsoft Quantum Development Kit which will include a new chemical simulation library developed in collaboration with Pacific Northwest National Laboratory (PNNL), a leader in both chemistry and data analytics. The library can be used in conjunction with NWChem, an open source, high-performance computational chemistry tool funded by the U.S. Department of Energy's Office of Science. Together, the chemistry library and NWChem will help enable quantum solutions and allow researchers and developers a higher-level of study and discovery as they tackle today's computationally complex chemistry problems.

"PNNL is excited to team with Microsoft to demonstrate how quantum computing can advance computational chemistry," says Steven Ashby, Director of PNNL. "This partnership draws on the complementary capabilities of the Microsoft Quantum Development Kit and NWChem, and the respective expertise in quantum algorithms and computational chemistry. Together, we can explore a variety of applications in areas such as the design of novel catalysts to drive efficiency in fertilizer productiona process that currently consumes two percent of the world's energy."

The Quantum Development Kit update will also bring capabilities of modern language design to Q# programming, such as support for IntelliSense in Visual Studio as well as new language capabilities that are valuable for quantum computing. More information on the release will be available later this year.

PNNL joins two additional collaborations we announced this year: the Dubai Electricity and Water Authority (DEWA) and Case Western Reserve University (CWRU), both demonstrating the promise of quantum computing and how the Quantum Development Kit enables solution development that tackles complex real-world challenges. With the goal of developing new quantum-based solutions to address problems including energy optimization and improving sustainability, DEWA is the first organization outside the U.S. to participate in the Microsoft Quantum program. With the goal of improving patient care, CWRU has leveraged Microsoft's quantum-inspired algorithms and the Quantum Development Kit to enhance their approach to detecting cancerous tumors. In just two months, this collaboration has explored better pulse sequences which can produce higher quality MRI scans resulting in faster and improved diagnostics.

"We can now solve problems that we’ve never been able to solve before. By applying these algorithms, we are now able to take a different approach to the most difficult problems in MRIsand we believe it will have a broad impact for patients," says Dr. Mark Griswold, professor of Radiology at CWRU.

Over the past year we've expanded our investment in quantum computing to include a vast network of theory and modeling, fabrication, growth, device development, and robust testing capabilities across the globe. The combination of these facilities enables us to incubate the next generation of innovative materials and design new devices needed for the industry's first enterprise-ready quantum computer. Pioneering capabilities include growing exotic materials, designing cryogenic controls, and building a hardware and software architecture and infrastructureeach critical components of our vision of the world's first enterprise-ready quantum computer accessible in Azure for the next generation of innovators.

We have established seven Microsoft Quantum labs across the US, Europe, and Australia. The seventh of these state-of-the-art labs opened its doors officially three days ago in Lyngby, at the Microsoft Development Center Copenhagen. This lab is one of a kind and focused on a quantum materials platform that forms a critical foundation for scalable quantum computation. The lab will tackle a common and central challenge in quantum computing: quantum state decoherence. The groundbreaking new lab will approach this fundamental problem by developing customized hardware that is designed to fabricate complete quantum networks while keeping all processing steps in an ultra-clean environment that mirrors that of the ultra-high vacuum of deep space.

Microsoft performs quantum research alongside some of the best and brightest minds at universities where we have established several of our Microsoft Quantum Labs. At these locations, our research teams are not only advancing Microsoft Quantum research goals, but they also serve as scientific collaborators and partners with other members of the quantum community, investing and contributing to fundamental research and scientific insights. This groundbreaking work manifests itself in the form of an impressive portfolio of scientific publicationsin the last year, our researchers have been in nearly 150 publications in the world's top-tier scientific journals. This research is paving a new road of fundamental breakthroughs toward our goal of delivering a scalable quantum computer.

In addition to our laboratories, we've established many scientific partnerships across the globe to deepen and expand our research investments in the US, Canada, Australia, Denmark, the Netherlands, Switzerland, Finland, Italy, Spain, and Austria. The partnerships augment our global coverage of the top research institutions, laboratories, and talent across the areas of physics, quantum theory, computer science, hardware, chemistry, and materials.

Over the last year, we've released industry-leading developer support for quantum computing through the Microsoft Quantum Development Kit. The Quantum Development Kit is designed for all types of developers who are eager to learn how to program quantum computers, while not assuming expertise in quantum physics. The Quantum Development Kit includes the Q# programming language, a quantum computer simulator, integration with Visual Studio and Visual Studio Code, an open source community, and a suite of documentation, tutorials, libraries, and sample algorithms. The Quantum Development Kit supports a broad and inclusive range of development platforms including Windows, Linux, and macOS and programming languages such as Python.

With downloads increasing every day, tens of thousands from around the globe are exploring the Quantum Developer Kit and experiencing the world of quantum computing, from startups to the enterprise and across academia, research, and design. This broad Microsoft quantum ecosystem is enabling problem solvers from various disciplines and skill levels to explore the world of quantum development to solve some of the planet's most complex challenges. Highlights this year include several developer events from Seattle to Zurich to Dubai, a global coding challenge for Q#, and self-paced tutorials called the Microsoft Quantum Katas.

Quantum computing holds the promise of solving many of today's otherwise unsolvable problems. The availability of a scalable quantum computer will unlock incredible potential by helping answer questions that cannot be addressed by today's computers in a realistic amount of time. We are excited about our progress towards our bold vision and believe in the limitless possibilities that will result from enabling developers with the power of quantum programming. Everyonewhether an engineer, enthusiast, student, or expert, everyone can explore the potential of quantum computing thanks to the power and accessibility of the Quantum Development Kit.

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]]>The post Developing a topological qubit appeared first on Microsoft Azure Quantum Blog.

]]>The fragile nature of qubits is well-known as one of the most significant hurdles in quantum computing. Even the slightest interference can cause qubits to collapse, making the solutions we're pursuing impossible to identify because the computations cannot be completed.

Microsoft is addressing this challenge by developing a topological qubit. Topological qubits are protected from noise due to their values existing at two distinct points, making our quantum computer more robust against outside interference.This increased stability will help the quantum computer scale to complete longer, more complex computations, bringing the solutions we need within reach.

Topology is a branch of mathematics describing structures that experience physical changes such as being bent, twisted, compacted, or stretched, yet still maintain the properties of the original form. When applied to quantum computing, topological properties create a level of protection that helps a qubit retain information despite what's happening in the environment. The topological qubit achieves this extra protection in two different ways:

**Electron fractionalization.**By splitting the electron, quantum information is stored in both halves, behaving similarly to data redundancy. If one halfof the electron runs into interference, there is still enough information stored in the other half to allow the computation to continue.**Ground state degeneracy.**Topological qubits are engineered to have two ground statesknown as ground state degeneracymaking them much more resistant to environmental noise. Normally, achieving this protection isn’t feasible because there’s no way to discriminate between the two ground states. However, topological systems can use braiding or measurement to distinguish the difference, allowing them to achieve this additional protection.

Currently years into the development of the topological qubit, the journey began with a single question, “Could a topological qubit be achieved”? Working with theory as a starting point, Microsoft brought together mathematicians, computer scientists, physicists, and engineers to explore possible approaches. These experts collaborated, discussed methods, and completed countless equations to take the first steps on the path toward realizing a topological qubit.

Modeling and experimentation work hand-in-hand as an ongoing, iterative cycle, guiding the design of the topological qubit. Throughout this process, the Microsoft team explored possible materials, ways to apply control structure, and methods to stabilize the topological qubit.

A team member proposed the use of a superconductor in conjunction with a strong magnetic field to create a topological phase of matteran approach that has been adopted toward realizing the topological qubit. While bridging these properties has been long-taught,it had never been done in such a controlled way prior to this work.

To create the exact surface layer needed for the qubit, chemical compounds are currently being grown in Microsoft labs using a technique called "selective area growth." Chosen for its atomic-level precision, this unique method can be described as spraying atoms in the exact arrangement needed to achieve the properties required.

The team continues testing functional accuracy through device simulation, to ensure that every qubit will be properly tuned, characterized, and validated.

Many fields of knowledge have come together to realize the topological qubit, including mathematics, theoretical physics, solid state physics, materials science, instrumentation and measurement technology, computer science, quantum algorithms, quantum error correction, and software applications development.

Bridging these fields has led to breakthrough techniques across all aspects of realizing a topological qubit, including:

**Theory and simulation****–**Turning a vision into reality by creating a rapid design, simulation, and prototyping process**Fabrication****–**Pioneering unique fabrication approaches and finding new ways to bridge properties**Materials growth**– Developing inventive methods to create materials using special growth techniques to create the exact properties required at nanoscale**Measurement and quantum control****–**Tuning devices for accuracy in function and measurement

At Microsoft, the development of the topological qubit continues, bringing us closer to scalable quantum computing and finding solutions to some of the world's most challenging problems.

Follow along on our journey to scalable quantum computing by signing up for the Microsoft Quantum newsletter.

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Quantum computers have the power to provide solutions to some of the world’s toughest problems. While many people assume that quantum computers will replace classical computers, in reality, both technologies will work together to solve these problems. It can be helpful to think of a quantum computer like a GPUa specialized processor used for applicable scenarios. Similarly, as classical computers run computations, the workloads or problems best suited for quantum could be processed by the quantum computer. From development to deployment, Microsoft is empowering the quantum revolution with a complete approach to quantum systems. This approach uses topological qubits, a type of qubit that allows the system to scale. The result is an integrated, scalable solution that combines both quantum and classical computing.

The process of building a quantum computer includes creating the raw materials needed to make topological quantum devices, fabricating the cold electronics and refrigeration systems, and developing the overall infrastructure needed to bring the solution to life. In addition, our system includes everything you need to program the quantum computer, including a control system, software, development tools, and Azure servicesa combination we refer to as our full quantum stack.

Because quantum and classical work together, Microsoft Azure is a perfect environment for quantum processing and deployment. With data stored in Azure, developers will be able to access quantum processing alongside classical processing, creating a streamlined experience.

Using the complete Microsoft quantum system, what would the start-to-finish experience look like?

Beginning with a problem you may be able to solve with a quantum algorithm

- You would start by building your solution in Visual Studio, using the tools found in the Microsoft Quantum Development Kit.
- Using Q#, a language created specifically for quantum development, you would write the code for your solution with the help of the extensive Microsoft quantum libraries.
- When your code is complete, you would run a quantum simulation to check for bugs and validate that your solution is ready for deployment.
- Once validated, you would be ready to run your solution on the quantum computer.
- Your quantum solution would be deployed from within Microsoft Azure, using the quantum computer as a co-processor. As many scenarios will use both quantum and classical processing, Azure will streamline workflows as real-time or batch applications, later connecting results directly into your business processes.

Together, this full quantum stack pairs with familiar tools to create an integrated, streamlined environment for quantum processing.

Quantum computers can help address some of the world's toughest problems, provided the quantum computer has enough high-quality qubits to find the solution. While the quantum systems of today may be able to add a high number of qubits, the *quality* of the qubits is the key factor in creating useful scale. From the cooling system to qubits to algorithms, scalability is a fundamental part of the Microsoft vision for quantum computing.

The topological qubit is a key ingredient in our scalable quantum system. Different from traditional qubits, a topological qubit is built in a way that automatically protects the information it holds and processes. Due to the fragile nature of conventional qubits, this protection offers a landmark improvement in performance, providing added stability and requiring fewer qubits overall. This critical benefit makes the ability to scale possible.

Microsoft has been working on scalable quantum computing for nearly two decades, creating its first quantum computing groupknown as Station Qin 2006. Investing in scalable quantum computing for over a decade, we have connected some of the brightest minds in the industry and academia to make this dream a reality. Blending physics, mathematics, engineering, and computer science, teams around the globe work daily to advance the development of the topological qubit and the Microsoft vision for quantum computing.

At Microsoft, we envision a future where quantum computing is available to a broad audience, scaling as needed to solve some of the world's toughest challenges. Our quantum approach begins within familiar tools you know and use such as Visual Studio. It provides development resources to build and simulate your quantum solutions. And it continues with deployment through Azure for a streamlined combination of both quantum and classical processing.

We invite you to:

- Follow the journey to scalable quantum computing by signing up for the Microsoft Quantum newsletter
- Download the Microsoft Quantum Development Kit
- For a deep dive in our approach, watch this video on Achieving practical quantum computing

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]]>The post Achieving practical quantum computing appeared first on Microsoft Azure Quantum Blog.

]]>This video starts with the basics and continues into deeper topics such as quantum gates, algorithms, and T factories. You’ll also get a brief preview of quantum teleportation, matrix algebra, and Q#, the quantum-focused programming language available in the Microsoft Quantum Development Kit.

Serving as an intro to the Microsoft quantum computing effort, this video makes an excellent primer for understanding what's involved in the journey toward scalable quantum computing.

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]]>As the path to build a quantum computer continues, challenges from across industries await solutions from this new computational power. One of the many examples of high-impact problems that can be solved on a quantum computer is developing a new alternative to fertilizer production. Making fertilizer requires a notable percentage of the world’s annual production of natural gas. This implies high cost, high energy waste, and substantial greenhouse emissions. Quantum computers can help identify a new alternative by analyzing nitrogenase, an enzyme in plants that converts nitrogen to ammonia naturally. To address this problem, a quantum computer would require at least 200 fault-free qubitsfar beyond the small quantum systems of today. In order to find a solution, quantum computers must scale up. The challenge, however, is that scaling a quantum computer isn’t merely as simple as adding more qubits.

Building a quantum computer differs greatly from building a classical computer. The underlying physics, the operating environment, and the engineering each pose their own obstacles. With so many unique challenges, how can a quantum computer scale in a way that makes it possible to solve some of the world’s most challenging problems?

Most quantum computers require temperatures colder than those found in deep space. To reach these temperatures, all the components and hardware are contained within a dilution refrigeratorhighly specialized equipment that cools the qubits to just above absolute zero. Because standard electronics don't work at these temperatures, a majority of quantum computers today use room-temperature control. With this method, controls on the outside of the refrigerator send signals through cables, communicating with the qubits inside. The challenge is that this method ultimately reaches a roadblock: the heat created by the sheer number of cables limits the output of signals, restraining the number of qubits that can be added.

As more control electronics are added, more effort is needed to maintain the very low temperature the system requires. Increasing both the size of the refrigerator and the cooling capacity is a potential option, however, this would require additional logistics to interface with the room temperature electronics, which may not be a feasible approach.

Another alternative would be to break the system into separate refrigerators. Unfortunately, this isn’t ideal either because the transfer of quantum data between the refrigerators is likely to be slow and inefficient.

At this stage in the development of quantum computers, size is therefore limited by the cooling capacity of the specialized refrigerator. Given these parameters, the electronics controlling the qubits must be as efficient as possible.

By nature, qubits are fragile. They require a precise environment and state to operate correctly, and they're highly prone to outside interference. This interference is referred to as 'noise', which is a consistent challenge and a well-known reality of quantum computing. As a result, error correction plays a significant role.

As a computation begins, the initial set of qubits in the quantum computer are referred to as 'physical qubits'. Error correction works by grouping many of these fragile physical qubits, which creates a smaller number of usable qubits that can remain immune to noise long enough to complete the computation. These stronger, more stable qubits used in the computation are referred to as 'logical qubits'.

In classical computing, noisy bits are fixed through duplication (parity and Hamming codes), which is a way to correct errors as they occur. A similar process occurs in quantum computing, but is more difficult to achieve. This results in significantly more physical qubits than the number of logical qubits required for the computation. The ratio of physical to logical qubits is influenced by two factors: 1) the type of qubits used in the quantum computer, and 2) the overall size of the quantum computation performed. And due to the known difficulty of scaling the system size, reducing the ratio of physical to logical qubits is critical. This means that instead of just aiming for more qubits, it is crucial to aim for better qubits.

The topological qubit is a type of qubit that offers more immunity to noise than many traditional types of qubits. Topological qubits are more robust against outside interference, meaning fewer total physical qubits are needed when compared to other quantum systems. With this improved performance, the ratio of physical to logical qubits is reduced, which in turn, creates the ability to scale.

As we know from Schrdinger’s cat, outside interactions can destroy quantum information. Any interaction from a stray particle, such as an electron, a photon, a cosmic ray, etc., can cause the quantum computer to decohere.

There is a way to prevent this: parts of the electron can be separated, creating an increased level of protection for the information stored. This is a form of topological protection known as a Majorana quasi-particle. The Majorana quasi-particle was predicted in 1937 and was detected for the first time in the Microsoft Quantum lab in the Netherlands in 2012. This separation of the quantum information creates a stable, robust building block for a qubit. The topological qubit provides a better foundation with lower error rates, reducing the ratio of physical to logical qubits. With this reduced ratio, more logical qubits are able to fit inside the refrigerator, creating the ability to scale.

If topological qubits were used in the example of nitrogenase simulation, the required 200 logical qubits would be built out of thousands of physical qubits. However, if more traditional types of qubits were used, tens or even hundreds of thousands of physical qubits would be needed to achieve 200 logical qubits. The topological qubit’s improved performance causes this dramatic difference; fewer physical qubits are needed to achieve the logical qubits required.

Developing a topological qubit is extremely challenging and is still underway, but these benefits make the pursuit well worth the effort.

A significant number of logical qubits are required to address some of the important problems currently unsolvable by today’s computers. Yet common approaches to quantum computing require massive numbers of physical qubits in order to reach these quantities of logical qubitscreating a huge roadblock to scalability. Instead, a topological approach to quantum computing requires far fewer physical qubits than other quantum systems, making scalability much more achievable.

Providing a more solid foundation, the topological approach offers robust, stable qubits, and helps to bring the solutions to some of our most challenging problems within reach.

- Follow along on our path to scalable quantum computing with the Microsoft Quantum newsletter
- Learn how we’re empowering the quantum revolution on the Microsoft Quantum website
- Get started with quantum development by downloading the Microsoft Quantum Development Kit

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