Computing

Nanomechanische resonatoren – Hoe quantumcomputing kan profiteren van deze piezo-elektrische apparaten

mm
Gepubliceerd op
Bijgewerkt op
Securities.io maintains rigorous editorial standards and may receive compensation from reviewed links. We are not a registered investment adviser and this is not investment advice. Please view our affiliate disclosure.

Miniaturizing Sensors

As our technology becomes increasingly precise, it also requires ever-shrinking devices. This is well known for semiconductor technology like chips, with 2 nm (nanometer) lithografie die nu door industriële leiders wordt getest zoals TSMC.

Bron: TSMC

Dit geldt ook voor mechanische onderdelen, waarbij de reactie niet primair elektrisch is, zoals bij halfgeleiders. Een sleutelelement is nano-schaal mechanische resonatoren. De zeer kleine afmeting van deze apparaten maakt ze zeer bruikbaar voor het meten van individuele deeltjes.

Tot nu toe is slechts een beperkte reeks niet-geleidend materiaal gebruikt om mechanische resonatoren te produceren. Dit is nu veranderd dankzij het werk van onderzoekers aan de Chalmers University of Technology (Zweden) en de Universiteit van Magdeburg (Duitsland).

Deze groep onderzoekers heeft een mechanisch resonator gemaakt van een nieuw materiaal, dat zowel uitstekende resonantie-eigenschappen heeft en tevens piezo-elektrisch is. Deze resultaten werden gepubliceerd in Advanced Materials, onder de titel “Nanomechanical Crystalline AlN Resonators with High-Quality Factors for Quantum Optoelectromechanics1”.

Nanomechanical Resonators

Resonatoren zijn componenten zoals stemvorken die kunnen trillen op specifieke frequenties. In het geval van de stemvork trilt deze op zijn resonantiefrequentie, waardoor een geluidsgolf binnen ons hoorbare bereik ontstaat.

Vandaag zijn resonatoren verkleind tot micrometer- en nanometerschaal. Deze kleine resonatoren werken op veel hogere frequenties dan grote, en zijn uiterst gevoelig. Dit maakt ze zeer goede sensoren voor metingen op microscopische schaal.

For example, such a nanoresonator can be used to measure the spins of single-proton or the gravity between small masses.

Making Resonators More Useful

Until now, most of the best nanomechanical resonators are made from tensile-strained silicon nitride. This is a material with exceptional mechanical qualities, making for a very good resonator. The problem is that silicon nitride is not magnetic, nor piezoelectric, and does not conduct electricity.

This is a problem to convert the mechanical resonance into an electric signal, or to control it directly. So overall, these silicon nitride resonators can only interact with other systems when another material is added on top of the silicon nitride.

The problem is that such an addition directly harms the performance of the resonator.

Instead, the researchers managed to create a nanomechanical resonator made of tensile-strained aluminum nitride. This material is piezoelectric, but it also displays excellent properties as a resonator, measured by a characteristic called the “mechanical quality factor” (Qm).

“De aluminium nitride resonator bereikte een kwaliteitsfactor van meer dan 10 miljoen. Dit suggereert dat trek-gestreste aluminium nitride een krachtig nieuw materiaalplatform kan zijn voor quantum-sensoren of quantum-transducers.

Witlef Wieczorek – Professor of Physics at the Department of Microtechnology and Nanoscience at Chalmers University of Technology.”

Piezo-elektrische materialen zijn een type materiaal dat van nature mechanische beweging omzet in elektrische signalen en omgekeerd.

Deze elektrische lading wordt geproduceerd door gedwongen asymmetrie: in piezo-elektrische materialen worden positieve en negatieve ladingen van elkaar gescheiden, terwijl ze in een symmetrisch patroon uitgelijnd blijven.  When mechanical stress is applied to the substance, this symmetry is lost, resulting in the production of an electric charge.

So contrary to previous versions of resonators, an aluminum nitride resonator can directly be interfaced with other nanoscale systems. And it could be used for direct readout in sensors.

How It Was Made

To develop this new type of resonator, the researchers created a highly stressed (tense) thin film of aluminum nitride 295 nm thick, by growing it on a substrate of silicon. The tension was “about 1GPa, the equivalent of balancing two elephants on a fingernail”.

They used a new resonator design, called trianguline, which looks like a fractal made with a central triangle-shaped pad.

The trianguline could be especially useful as it can maintain a single quantum coherent oscillation at room temperature. This would make it a lot easier to employ in quantum technology.

The Next Step

As a first-of-a-kind prototype, it is likely that the aluminum nitride resonator presented here can still be improved further.

The first part will be to make it with an even higher quality factor, making it more sensitive and useful. The next step will be to experiment and find how to reliably adapt the design so it can be using piezoelectricity for quantum sensing applications.

Applications

The most obvious application would be in quantum computing. Most quantum computers work by having the quantum bits (qubits) properties measured.

Qubits can exist in multiple states simultaneously thanks to two quantum properties: superpositie and verstrengeling.

  • Superpositie maakt het mogelijk dat qubits zowel 0 als 1 tegelijk kunnen vertegenwoordigen, waardoor de hoeveelheid verwerkte data exponentieel toeneemt ten opzichte van klassieke bits.
  • Verstrengeling verbindt qubits op een manier dat de toestand van één qubit onmiddellijk een andere kan beïnvloeden, zelfs over grote afstanden.

These properties enable QPUs to solve highly complex problems much faster than classical computers by exploring multiple solutions simultaneously.

However, qubits are extremely fragile, and measuring their properties is not an easy task. A room temperature resonator that is also piezoelectric could be a game changer, both in terms of performance and costs.

This could make aluminum nitride resonators a key part in the development of Quantum Processing Units able to replace our current CPU, a topic we discussed in further details in “Quantum Processing Units (QPUs): The Future of Computing” and in “The Current State of Quantum Computing”.

Other applications could stem from the resonators’ extreme precision, in niche applications low noise and long coherence time are required, like mirror suspensions, quantum cavity optomechanical devices, or nanomechanical sensors, all useful for nanodevices like LEDs, photonics computing, etc.

This is another example of how important piezoelectric materials could be in future technologies. You can learn more about this topic from some of our articles covering these materials:

Investing In Nanotechnology

Nanotechnologie wordt een groeiende sector buiten de productie van halfgeleiders, met beloften van wondermaterialen voor de lucht- en ruimtevaart, biotechnologie, energie- en chemische industrieën.

You can invest in nanotech companies through many brokers, and you can find here, on securities.io, our recommendations for the best brokers in de VS, Canada, Australië, het VK, en ook in vele andere landen.

If you are not interested in picking specific nanotech companies, you can also look into nanotechnology ETFs like the ProShares Nanotechnology ETF (TINY) or the Direxion Nanotechnology ETF (TYNE) which will provide a more diversified exposure to capitalize on quantum computing & nanotech stocks.

Or you can look at our list of the “Top 10 Nanotechnologie Aandelen” and 5 Beste Quantum Computing Bedrijven.

Resonator Company

(SITM )

As our computers and electronics become more complex, having exact measurements becomes even more important, in some cases a matter of life or death.

This is the focus of SiTime, a company centered around accurate time measurement using silicon technology. This is similar to how quartz crystals are used in watches (a 70-year-old technology), except for its superior performances:

  • Extreme resistance to interferences from shock, vibration, changes in temperature, jitter, and noise.
  • Small size and low power requirements.
  • Programmable and higher performance.

Bron: SiTimes

SiTime is the company responsible for creating the concept of “precision timing,” a segment growing 30-35% a year and on which the company has a 90% market share.

As a “fabless” semiconductor company, SiTime focuses on developing its IPs, leaving the actual manufacturing to industry leaders, a similar business model to Nvidia for its GPUs and AI chips.

More precise time measurement through precision timing is becoming a must, as new computing and telecom technologies are moving very fast:

  • 5G-connectiviteit is 10x sneller dan 4G
  • Datacenters werken ook 10x sneller dan een paar jaar geleden, en staan klaar om te versnellen met groeiende AI-toepassingen.
  • Automotive en andere voertuigen integreren tegenwoordig veel meer elektronica, en vóór de komst van robotaxi’s (alle autonomie-niveaus boven 2 hebben precisietiming nodig).
    • SiTime biedt de “FailSafe” technologie waarbij het enkele apparaat resonatoren, oscillatoren, klokfuncties en geavanceerde veiligheidsmechanismen voor timing in autonome voertuigen integreert. Massaproductie zal pas in 2025 beginnen.
  • De lucht- en ruimtevaartsector groeit snel met bedrijven zoals SpaceX die vooroplopen zowel in meer gelanceerd materiaal als in nieuwe toepassingen zoals lage-latentie ruimtegebaseerd internet.

From a startup with little revenues in 2019 (mostly from oscillators) and launching its first resonators in 2020, SiTime has grown very quickly, increasing at once revenues, gross margin and operating margin.

Bron: SiTimes

This followed the overall growth of the Serviceable Addressable Market (SAM) for SiTime from $1B in 2021 to $4B in 2024, as part of the overall larger $10B “timing market”.

Bron: SiTimes

SiTime has invested over $500M in R&D cumulatively since inception. The micro-electromechanical systems (MEMS) industry tends to favor a structure where one company almost entirely dominates a segment, as the barriers to entry are high (R&D costs, technical expertise, patents) and clients tend to stick to the industry leaders.

This puts SiTime as the leader of “timing MEMS”, alongside other companies like Broadcom (AVGO ) for radio frequency or Bosch for inertial sensors (SiTime was een spin-off van Bosch, before being bought by the Japanese company Megachips and listed on NASDAQ in 2019).

With AI data centers, 5G deployment, satellite telecommunication, and self-driving vehicles all exponentially growing sectors, SiTime is well positioned to itself grow very quickly, and become a less-known but vital cornerstone of the ongoing connectivity & AI revolution.

Studieverwijzing:

1. Ciers, A., Jung, A., Ciers, J., Nindito, L. R., Pfeifer, H., Dadgar, A., Strittmatter, A., & Wieczorek, W. (2024). Nanomechanical crystalline AlN resonators with high quality factors for quantum optoelectromechanics. Advanced Materials, 36(44), 202403155. https://doi.org/10.1002/adma.202403155

mm

Jonathan is een voormalig onderzoeker in de biochemie die werkte aan genetische analyse en klinische onderzoeken. Hij is nu een aandelenanalist en financieel schrijver met een focus op innovatie, marktcycli en geopolitiek in zijn publicatie The Eurasian Century.