Shail Dave

I just finished reading “Microwave Techniques in Superconducting Quantum Computers” by Alan Salari, and it's a fantastic, highly recommended book. Quantum hardware engineers need expertise in quantum mechanics, qubit design, microwave techniques, data acquisition, and cryogenic engineering. This book is perhaps the first to comprehensively cover all these topics, offering practical techniques grounded in solid theory for designing and operating superconducting quantum computing hardware. I've been fascinated by quantum physics and especially quantum computing for many years, but most books I’ve found focused either on quantum computing itself or the mathematical background for quantum algorithms. So, I was thrilled to discover this book, which 𝗮𝗰𝘁𝘂𝗮𝗹𝗹𝘆 shows and explains how the hardware of a real quantum computer is built. ◼ The book starts with a fundamental introduction to quantum physics and qubit manipulation for quantum computing. Then, it dives into the practical aspects, explaining how superconducting qubits are built and coupled to their environment. For the first time, I encountered detailed drawings of Josephson junctions, transmon qubits, and how they are integrated within microwave resonators for control and readout. The diagrams and explanations are outstanding—they made the concepts very clear. ◼ It also covers key microwave systems and components, especially in relation to qubit control and readout. Even as an experienced RF engineer, I learned new concepts, like how solutions to Maxwell's equations vary with system length and how thermal noise equations break down at very low temperatures—crucial for working with qubits in cryogenic environments. ◼ The book also delves into the latest cryogenic technology, which is essential if you’re going to engineer quantum hardware. Working with extremely low temperatures is a must in this field. ◼ Finally, the book ties everything together, showing how all the subcomponents connect to create a quantum computer. It details how the qubit is mounted in the coldest part of a cryogenic system (inside the mixing chamber), how the different RF cables are installed and connected to deliver the necessary microwave signals for qubit control and readout, how to perform a microwave link budget for qubit control, and when to use attenuators and circulators. I was delighted to see how my microwave engineering knowledge applies to this exciting technology. If you're looking to start learning about the future of quantum hardware, this book is the best place to begin. Alan Salari has done tremendous work, and while predicting the future is always tricky, I believe this book will become a classic in its domain, much like Pozar for microwave engineering, Sedra and Smith for IC design, and The Art of Electronics. 🔸 I now know that I want to become a quantum hardware engineer.

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Chip Level Performance and Security Intel Corporation decision to phase out Hyper-Threading in their upcoming 15th Gen Arrow Lake processors indeed marks a significant performance and security shift. This smart move is primarily driven by Intel's findings that traditional Hyper-Threading didn't deliver the expected performance improvements with their new architectures. Instead, they are exploring new approaches like "Rentable Units" for future generations, such as the 16th Gen Panther Lake. Chip level Security concerns have also played a crucial role in this decision. Hyper-Threading has been associated with vulnerabilities like MDS attacks (Microarchitectural Data Sampling), which include exploits like ZombieLoad, RIDL, Meltdown and Spectrem, and Fallout, etc.. These vulnerabilities arise from the sharing of resources between threads on the same CPU core, potentially exposing systems to data inference attacks. The proactive steps by operating systems like OpenBSD to disable Hyper-Threading highlight the seriousness of these security risks. Despite potential performance benefits, the decision underscores Intel's commitment to enhancing both performance and security in their processors moving forward. We look forward to seeing better innovations and technology from Intel as they lead in this new era of CPU innovation and generation. Resource: Hardware Times: https://lnkd.in/gCvB9_Sr Hyper-Threading and the Processor Pipeline: https://lnkd.in/gGeTirPt

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https://lnkd.in/gRiPD7tN Several career Intel Corporation ex-colleagues would be forced into layoffs in the next few days because of the mess that it has gotten into thanks to its top management for years, accelerated in last three years. An Intel Corporation representative Jeff Rittener told US senate recently, under oath, that Pat Gelsinger was paid 40% more in 2023 while Intel was in deep shit and gave employees 5% base pay cuts and other cuts to benefits and bonuses, than he was paid in 2021 when Intel was having some of its best times in recent history. So Pat took the revenue down some 1.4x over two years, while his own income from Intel increased 1.4x over the same two years. When Rittener was asked how Intel Corporation management has the gall to layoff so many Americans while taking US govt money, he replied "Intel hasn't taken any money" - I'm sure this would be news to many. In fact it got more ridiculous - when asked why has Intel continued to invest in Chinese AI and Semiconductors companies through it's venture arm, Rittener replied that Intel wants to benefit from developments in that nation. This when Pat Gelsinger can't be shut up about Semiconductors manufacturing imbalance between Asia and the west, when he is begging for CHIPS Act money. Somehow China isn't in Asia according to his Atlas. Either that or he thinks China having Semiconductors advances is preferable to US allies Taiwan and South Korea having those advances The whole video is here https://lnkd.in/gxrNJgZ5 and here https://lnkd.in/g5VSB3tp

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Optimizing Verification with UVM and SystemC In my experience working with self-optimized UVM test benches, I've found them to be a transformative approach to semiconductor verification. Integrating SystemC reference models has been particularly impactful, allowing for a more efficient and precise verification process. These models provide a high-level abstraction of the design-under-test (DUT), enabling faster simulation and earlier detection of potential issues. One of the key benefits I've observed is the ability to adapt test sequences and stimulus generation dynamically. By leveraging the behavioral accuracy of SystemC models, the test bench can focus on under-tested or critical areas of the DUT, significantly improving coverage without increasing the number of tests. This adaptability is crucial, especially as designs grow in complexity. Moreover, the feedback mechanisms within the UVM test bench, when cross-referenced with SystemC models, enhance the accuracy of bug detection. The test bench can quickly identify discrepancies between the DUT and the expected behavior outlined in the SystemC model, allowing for rapid iteration and refinement. However, integrating SystemC into UVM isn't without challenges. It requires a deep understanding of both methodologies and can be resource-intensive. Debugging can also be more complex due to the additional abstraction layer. Despite these challenges, the benefits—particularly in terms of reducing verification time and improving overall coverage—make self-optimized UVM test benches with SystemC models an invaluable tool in modern verification flows. #VLSI #UVM #SyestemC

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Dive into Karl Freund's article on the rise of physical AI in robotics. Learn how leading companies are leveraging NVIDIA technologies to transform the industry, along with recent advancements and breakthroughs.

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Qualcomm makes a bid for Intel Corporation was in news two weeks ago also https://lnkd.in/gyi56YUp There are scant details here but given what is going on with Intel's cashflows and Intel Foundry, and also the fact that Qualcomm has had less than no interest in Intel's manufacturing for nearly three years now, I am convinced that all Qualcomm really wants is Intel's CCG (Client Computing Group) PC/laptop business. They may be interested somewhat in servers too, but have absolutely no interest in the Foundry. Qualcomm tried hard to enter the PC marketnwith Arm architecture #snapdragon PC chips, which also got a great reception initially. However reports indicate that sales of Qualcomm based #Windows PCs have been tepid recently and the problems of emulating x86 applications on ARM are still persistent despite what is now a longer than a decade old effort. Qualcomm's existing businesses are focused mainly in Smartphone industry and have little chance of growing fast now, given that industry's maturity. But Qualcomm will have a shot at growing faster if it can capture the PC pie.

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