Given the impending timeline of developing good-quality quantum processing units, it is time to rethink the approach to advance quantum computing research. Rather than waiting for quantum hardware technologies to mature, we need to start assessing in tandem the impact of the occurrence of quantum computing, or rather Quantum Computing Logic (QC-Logic), on various scientific fields. This is where the subtitle comes from. A new scientific revolution is unfolding. In making real scientific progress, we need to use an additional and complementary approach, which the NISQ program or any follow-up approach does not propose. We must be aware that defining, implementing, and testing quantum concepts in any field is tremendous work. The main reason is that QC initiates an overall revolution in all scientific fields, and how those machines will be used in daily life is a very big challenge. That is why we propose a complete update of the first PISQ paper. We still advocate the additional PISQ approach: Perfect Intermediate-Scale Quantum computing based on a well-established concept of perfect qubits. We expand the quantum road map with (N)FTQC, which stands for (Non) Fault-Tolerant Quantum Computing. This will allow researchers to focus exclusively on developing new applications by defining the algorithms in terms of perfect qubits and evaluating them in two ways. Either executed on quantum computing simulators executed on supercomputers or hardware-based qubit chips. This approach will be explained in this paper. Our planet needs a long-term vision and solution. It will enable universities and companies alike to accelerate the development of new quantum algorithms, build the necessary know-how, and thus address one of the key bottlenecks within the quantum industry: the lack of talent to develop well-tested quantum applications.
Given the impending timeline of developing good-quality quantum processing units, it is time to rethink the approach to advance quantum computing research. Rather than waiting for quantum hardware technologies to mature, we need to start assessing in tandem the impact of the occurrence of quantum computing, or rather Quantum Computing Logic (QC-Logic), on various scientific fields. This is where the subtitle comes from. A new scientific revolution is unfolding. In making real scientific progress, we need to use an additional and complementary approach, which the NISQ program or any follow-up approach does not propose. We must be aware that defining, implementing, and testing quantum concepts in any field is tremendous work. The main reason is that QC initiates an overall revolution in all scientific fields, and how those machines will be used in daily life is a very big challenge. That is why we propose a complete update of the first PISQ paper. We still advocate the additional PISQ approach: Perfect Intermediate-Scale Quantum computing based on a well-established concept of perfect qubits. We expand the quantum road map with (N)FTQC, which stands for (Non) Fault-Tolerant Quantum Computing. This will allow researchers to focus exclusively on developing new applications by defining the algorithms in terms of perfect qubits and evaluating them in two ways. Either executed on quantum computing simulators executed on supercomputers or hardware-based qubit chips. This approach will be explained in this paper. Our planet needs a long-term vision and solution. It will enable universities and companies alike to accelerate the development of new quantum algorithms, build the necessary know-how, and thus address one of the key bottlenecks within the quantum industry: the lack of talent to develop well-tested quantum applications.
Given the impeding timeline of developing good quality quantum processing units, it is the moment to rethink the approach to advance quantum computing research. Rather than waiting for quantum hardware technologies to mature, we need to start assessing in tandem the impact of the occurrence of quantum computing in various scientific fields. However, to this purpose, we need to use a complementary but quite different approach than proposed by the NISQ vision, which is heavily focused on and burdened by the engineering challenges. That is why we propose and advocate the PISQ approach: Perfect Intermediate Scale Quantum computing based on the already known concept of perfect qubits. This will allow researchers to focus much more on the development of new applications by defining the algorithms in terms of perfect qubits and evaluate them on quantum computing simulators that are executed on supercomputers. It is not the long-term solution but will currently allow universities to research on quantum logic and algorithms and companies can already start developing their internal know-how on quantum solutions.
One of the main drivers for growing the field of quantum computation has been the prospect of creating a quantum computer capable of carrying out Shor's algorithm for huge numbers.Nonetheless, it is critical to recognise that quantum computers will probably only significantly speed up a small subset of issues if one wants to acquire a more comprehensive perspective on them.Building a system that can accommodate a lot of qubits while preserving stability and coherence is one of the biggest problems in quantum computing.Due to their extreme sensitivity to noise and mistakes, quantum systems are particularly susceptible to computing errors.Building a usable quantum computer requires error mitigation and correction, but the techniques for doing this are still in the early phases of research.In quantum computing, all processes and schemes must be reversible in accordance with the law of unitary development.The circuit model is taken into account in the NISQ framework, but there is also the one-way or measurement-based quantum computation approach, which is not reversible but is demonstrated to be comparable to the circuit model.Noisy suggests that the computing capacity of such quantum computers is constrained because of sufficiently high error and decoherence rates.While they are likely too huge to be replicated by traditional computers using brute force, Intermediate-Scale suggests that they are still too small to be mistake corrected, which also adds to the preceding argument about how noisy they are.P stands for the usage of perfect qubits with perfect quantum gates and no decoherence.The capability to control and protect our qubits in a quantum computer to the degree necessary to run such algorithms is commonly described as fault-tolerant quantum computation.This review paper examines the numerous quantum computing strategies, such as Noisy Intermediate Scale Computing (NISQ) , Perfect Intermediate Scale Computing (PISQ), and Fault Tolerant Intermediate Scale Computing (FTISQ), as well as potential future lines of inquiry.
The transition from classical to quantum computation marks a shift from deterministic binary logic to a probabilistic, entanglement‑driven framework able to address problems beyond classical reach. Today’s Noisy Intermediate ‑ Scale Quantum era features devices that lack full error correction yet already point toward larger, modular systems designed for fault‑tolerant operation. This paper examines the evolving paradigm shift from classical and NISQ ‑ era machines toward practical fault‑tolerant quantum computing, focusing on how advances in physical qubit technologies, control architectures, and error‑correction strategies are converging to bridge noisy prototypes and scalable, useful machines. We synthesize insights from historical semiconductor scaling trends, contemporary roadmaps from leading institutions and industry, and emerging modular designs with real‑time error decoding. Our analysis shows that while challenges around decoherence, connectivity, and classical co‑processing remain, coordinated progress in hardware, control, and software is laying a coherent foundation for future quantum platforms. The work concludes that quantum computing is maturing into a strategically significant paradigm, poised to redefine the limits of computation in simulation, optimization, and secure communication.
The field of quantum computing has evolved into a large interdisciplinary community where significant resources are invested worldwide. As a result, accelerated progress is achieved and we are at the beginning of a new age of computation, developing programmable quantum systems towards universal quantum computers. Quantum computers promise to solve certain mathematical problems that are intractable to classical computers. Quantum computing systems are built from the bottom up reaching the limits of what can be classically simulated. The IBM Quantum Development Roadmap describes our vision of creating a quantum computing ecosystem delivering quantum applications through the cloud. This requires developing the entire quantum computing stack starting from the qubit and quantum processor technology, control electronics to software, algorithms and applications for quantum computing, implemented in the cloud and integrated with high performance computing. In this presentation the recent developments of our quantum computing systems and the scientific advances that enabled scaling superconducting quantum processors to 127 qubits are presented. Besides scale, also quality and speed will be discussed building the key metric for measuring the performance of quantum computation. Examples of applications where the computational power of quantum computing could make a difference are provided.
Abstract Quantum computers have made extraordinary progress over the past decade, and significant milestones have been achieved along the path of pursuing universal fault-tolerant quantum computers. Quantum advantage, the tipping point heralding the quantum era, has been accomplished along with several waves of breakthroughs. Quantum hardware has become more integrated and architectural compared to its toddler days. The controlling precision of various physical systems is pushed beyond the fault-tolerant threshold. Meanwhile, quantum computation research has established a new norm by embracing industrialization and commercialization. The joint power of governments, private investors, and tech companies has significantly shaped a new vibrant environment that accelerates the development of this field, now at the beginning of the noisy intermediate-scale quantum era. Here, we first discuss the progress achieved in the field of quantum computation by reviewing the most important algorithms and advances in the most promising technical routes, and then summarizing the next-stage challenges. Furthermore, we illustrate our confidence that solid foundations have been built for the fault-tolerant quantum computer and our optimism that the emergence of quantum killer applications essential for human society shall happen in the future.
A paradigm shift in computation is being brought about by quantum computing, which uses the concepts of quantum mechanics to tackle problems that even the most powerful conventional supercomputers cannot solve. This review provides an in-depth overview of the field, covering everything from basic concepts to the cutting edge. The three fundamental building blocks of quantum processing—the qubit, superposition, and entanglement—are first described.These ideas enable quantum computers to concurrently explore large computational domains. After that, the paper examines the various physical implementations, highlighting the advantages and disadvantages of the top hardware platforms, such as neutral atoms, trapped ions, photonic systems, and superconducting circuits, in terms of coherence and scalability. Shor's method for integer factorization and Grover's algorithm for unstructured search are two examples of groundbreaking quantum algorithms that are highlighted for their potential to achieve exponential and quadratic speedups over their classical counterparts. We also examine how programming languages that bridge the gap between abstract algorithms and physical hardware are being developed, as well as the new quantum software stack. The paper also explores how quantum computing can revolutionize a number of fields, such as machine learning, materials research, medication development, and cryptography. subsequently, we discuss two of the biggest challenges impeding the development of large-scale, fault-tolerant quantum computers: the requirement for robust quantum error correction and decoherence. In the end, a view of the current period of Noisy Intermediate-Scale Quantum (NISQ) and the path towards quantum advantage is presented. Researchers, students, and professionals looking for a comprehensive grasp of this quickly developing and revolutionary topic are expected to find this review to be an invaluable asset.