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16. Potential Quantum Winners

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16. Potential Quantum Winners

Go with nature if you are trying to simulate nature. Here's who I am betting on.

Gautam Bahal
Nov 16, 2021
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16. Potential Quantum Winners

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There are several different approaches to quantum computing. However, at the heart of it all, they can be split into two camps: approaches that use (a) Natural qubits and (b) Synthetic qubits. Natural qubit approaches use qubits from nature: atoms, ions (i.e. a charged atom) and photons. Synthetic qubits are man-made and in solid state.

One of the reasons many QC pioneering companies gravitated to the synthetic (“superconducting”) qubit approach was the similarity to classical computing and the belief that existing silicon fabrication expertise could be leveraged for building QCs. Thus, QC behemoths like IBM and Google invested heavily into superconducting technology. They continue to do so today, along with Amazon and start-ups like Rigetti. Microsoft and Intel invested in to other types of synthetic qubit approaches (Silicon Quantum Dots for Intel and Topological Qubits for Microsoft). Google and IBM are considered far and away the leaders within synthetic qubits.

While Superconducting benefits from being based on familiar silicon technologies; there are some serious scale-up challenges involved:

  1. Manufacturing imperfections mean that qubits are not always exactly the same, introducing error into the quantum system. Big, big problem when working with delicate quantum mechanics.

  2. The connectivity between qubits is localised and “hard-wired”, creating further noise in the system and making scaling-up with a large number of qubits very difficult.

  3. To maintain their quantumness, they require a cryogenic environment at near absolute zero temperatures (i.e. -459.7 Fahrenheit) in a dilution refrigerator. The scale-up challenges are huge, as they may need football field sized array of these (very expensive) fridges in the path to scaling up.

There are some who think these challenges are insurmountable. This is also why many believe that scaled-up QCs will never see the light of day, as superconducting has proven very complex to scale up, and all the high profile players in the industry bet on this technology. This is why many people in tech continue to be bearish on QC as a whole - they associate QC only with superconducting, and have seen it fail to deliver over the years.

On a philosophical level, it seems to me that if you are trying to simulate nature itself, shouldn’t you use nature’s raw material if you can? Why not use actual natural quantum systems rather than make (imperfect) synthetic ones which are tiny but still contain millions/billions of atoms.

This is why I am much more bullish on approaches that use nature as the raw material. These approaches are mostly followed by start-ups. Within natural qubits, the “trapped-ion” approach is the most mature and tested. I will focus on the trapped-ion approach and the front-runner in that technology (IonQ) but for fullness the natural approaches are:

  1. Trapped ions: IonQ and Honeywell

  2. Neutral atoms: ColdQuanta and Atom Computing

  3. Photonics: PsiQuantum and Xanadu

Photononics (i.e. taking particles of light as the qubit) is very promising but extremely challenging. Among other serious challenges, they need to figure out how to have high quality storage, given photons travel at the speed of light, and are thus obviously hard to control!

Which brings me to the star of the show: trapped-ions and in particular IonQ. Like other natural qubits, ions are perfect by nature, so perfect that they are used in atomic clocks. Each atom/ion is perfectly replicable (Ytterbium atoms in the case of IonQ); nature doesn’t do manufacturing defects between atoms of the same element. This has a series of benefits: all to all qubit connectivity, high qubit stability, high gate fidelities, among others.

This can’t be emphasised enough: the actual “quantumness” of the system used here is perfect - it’s nature itself! The challenge is more in scaling up the engineering. The main issue facing the superconducting folks is that they can’t get the quantum mechanics right. They need breakthroughs is physics to make any progress, and that’s why they have been stuck.

The trapped-ion approach also has challenges, but they do not need any spectacular breakthroughs in physics. Their “physics” is done by nature. They need to get their laser technology and then their eventual photonic interconnects right for the scale-up, but that seems easier than catching light or manufacturing the perfect qubit from silicon. I know I am oversimplifying here, but I don’t want to get too technical here.

And so to IonQ, the leader in trapped-ion QCs, and one of the best quantum computing companies overall. Here’s why I like IonQ:

  1. Great (maybe best) team: The founders (Chris Monroe and JungSang Kim) are among the most cited academicians in QC, and are leveraging their decades of academic research to benefit IonQ. They have thought hard about scaling QCs and in fact wrote a great paper on it in all the way back in 2013. Having weighed all approaches, they went with trapped-ions.

  2. Unbelievable investor list: Google, Amazon, Bill Gates’ Breakthrough Energy Ventures, Michael Dell, Samsung, Hyundai, Kia, SilverLake, Airbus, Lockheed Martin, NEA, Softbank are all investors in IonQ. I have not seen a better investor list for any company I have ever tracked.

  3. Execution: IonQ has a detailed technical road-map and they are already executing extremely well. Their scale-up plan actually states that their systems will get smaller and cheaper. They claim to have the world’s most powerful quantum computer. The 32 qubit system, with 22 algorithmic qubits. Remember it’s always about logical or algorithmic qubits. The superconducting folks will always talk about larger raw qubit counts, but that is meaningless if they have so many errors and imperfections. You need qubits that work. Read more here.

  4. Cloud Partners: IonQ is the only QC company with it’s systems on all 3 major cloud providers: Amazon, Microsoft and Google. That is significant validation of their technology.

  5. Early customers: Goldman Sachs, Fidelity, Dow and others are already working with IonQ. Even though the systems are not powerful enough to beat classical supercomputers yet, these early customers want to make sure they are ready when the time comes. Interesting fact: Will Zeng, the head of Goldman’s QC team used to work at Rigetti - yet he chose IonQ to work with Goldman.

  6. It is publicly traded, which always helps! IonQ listed on the NYSE via a SPAC merger a few months ago.

I may be wrong about IonQ, but I like the risk-reward odds here (especially when we bought it at the $10 SPAC price. It has since moved up). I think it’s pretty binary (irony!): it will either be a very, very large company or go to zero (or get acquired in the middle I suppose). There will be other QC opportunities in the future too, but IonQ is a good start.

DISCLAIMER: I (AND MY FAMILY) OWN SHARES IN IONQ. THIS IS NOT INVESTMENT ADVICE. PLEASE DO YOUR OWN DUE DILLIGENCE. THIS IS MERELY A CONTINUATION OF MY SERIES ON QUANTUM.

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16. Potential Quantum Winners

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