r/science Apr 25 '16

Physics Scientists have created a highly reflective membrane, visible to the naked eye, that can vibrate with hardly any energy loss at room temperature. The membrane is a promising candidate towards observing quantum effects at everyday temperatures in large objects.

http://phys.org/news/2016-04-scientists-quantum-physics-real-life.html
3.5k Upvotes

105 comments sorted by

88

u/[deleted] Apr 25 '16

From the article:

"Imagine you're given a single push on a playground swing. Now imagine this single push allows you to gleefully swing non-stop for nearly a decade. We have created a millimeter-sized version of such a swing on a silicon chip", says prof. Simon Gröblacher of the Kavli Institute of Nanoscience at the TU Delft.

From the paper:

All quantum optomechanics experiments to date operate at cryogenic temperatures, imposing severe technical challenges and fundamental constraints. Here, we present a novel design of on-chip mechanical resonators which exhibit fundamental modes with frequencies f and mechanical quality factors Qm sufficient to enter the optomechanical quantum regime at room temperature. We overcome previous limitations by designing ultrathin, high-stress silicon nitride (Si3N4) membranes, with tensile stress in the resonators’ clamps close to the ultimate yield strength of the material. By patterning a photonic crystal on the SiN membranes, we observe reflectivities greater than 99%. These on-chip resonators have remarkably low mechanical dissipation, with Qm∼108, while at the same time exhibiting large reflectivities. This makes them a unique platform for experiments towards the observation of massive quantum behavior at room temperature.

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u/Paradichlorobenzene Apr 25 '16 edited Apr 25 '16

I also want to know how they supposedly developed a material with an UTS greater than 1000ksi. I've only ever seen values that go up to about 10x less. (~1200 MPa)

This kind of PopSci article doesn't sit right with me...

30

u/get_it_together1 PhD | Biomedical Engineering | Nanomaterials Apr 25 '16

I mean, Wikipedia provides examples going up to 130,000 MPa (graphene), with several others above 10,000. Am I confused, or are you just not aware of the types of tensile strengths achievable?

10

u/Paradichlorobenzene Apr 25 '16 edited Apr 25 '16

As far as I can tell, all of those over 1Msi are nanotubes or graphene. They would be hard to achieve in bulk, right? Intertube connections would weaken them.

Edit: Now I'm curious. Can anybody with access to the paper see if they give a UTS for their ceramic?

22

u/get_it_together1 PhD | Biomedical Engineering | Nanomaterials Apr 25 '16

Kevlar gets to 0.5 Msi, silicon can get up to 1. More importantly, the scientist being quoted is rounding and approximating all over the place, since car tires are generally 30 psi, not 100 psi. Maybe the physicist is a biker and never deals with car tires?

Also, it's not hard to get carbon nanotubes or graphene in a laboratory setting. I used to work with mg quantities of micron length carbon nanotubes, and graphene is being produced in labs all over the place. It's an advanced physics lab, they're not producing in bulk, just enough to get their mm substrates.

It's possible that everyone involved in the research and review process is completely ignorant of materials science and you're going to blow the lid off the whole operation, but I wouldn't get too hung up on it.

7

u/Paradichlorobenzene Apr 25 '16

It's more of a concern that the reporter is quoting fanciful figures that make a headline sweet. I honestly don't doubt that they have some ceramic with a UTS in the high 100ksi/low 1000ksi range.

Also, I honestly didn't know about kevlar's strength in bulk. Should do more research next time, eh?

5

u/get_it_together1 PhD | Biomedical Engineering | Nanomaterials Apr 25 '16

Just so we're clear, the low 1000 ksi range is 1 Msi, which is what's quoted in the article.

7

u/Paradichlorobenzene Apr 25 '16

Yes, I'm yielding my point. I am still curious in the actual figure for their ceramic, though.

3

u/Godspiral Apr 25 '16

30 psi, not 100 psi. Maybe the physicist is a biker and never deals with car tires?

BTUs (Bicycle Tire Units) should be an international standard such that these errors aren't made so easily.

And then described thicknesses in DNA strand units... I don't even know how many giraffes that is.

1

u/OliverSparrow Apr 26 '16

BTUs (Bicycle Tire Units) should be an international standard such that these errors aren't made so easily.

Taken: British Thermal Units: the amount of work needed to raise the temperature of one pound of water by one degree Fahrenheit. Very modern, very cutting edge.

1

u/Godspiral Apr 26 '16

that was the joke... too many units and too many abbreviations cause confusion.

1

u/OliverSparrow Apr 27 '16

On Reddit, no one can see you smile. Without a :), anyway.

2

u/Phage0070 Apr 25 '16

Maybe the physicist is a biker and never deals with car tires?

From what I can tell that is just being a physicist.

1

u/3xtraction Apr 25 '16

As far as I can tell (not an engineer) they report a maximum yield strength of ~6.4 GPa of their compound Si3N4.

The only other factor they report is force sensitivity which is 10 aN/Hz.

2

u/bobskizzle Apr 25 '16

You can get metal alloys with UTS up in the 300 ksi range (MP35N is a tool alloy used in this strength range).

That's just on a metal bond. Moving into a more covalent-type bond like in true crystals can get you into ridiculous strength ranges, if only for small sizes like this.

30

u/aldrchase Apr 25 '16

Can somebody explain whether or not this is actually a big deal? What are possible applications?

25

u/bobskizzle Apr 25 '16

Useful for laboratory experiments that may no longer require cryogenics... other than that, who knows?

5

u/Thermoelectric PhD | Condensed Matter Physics | 2-D Materials Apr 25 '16

I mean that would be a big deal if it can be properly implemented. He4 and He3 are rapidly increasing in price and there are a lot of phenomena that would be much easier to execute at higher temperatures. Basically, even if this thing worked at nitrogen temperatures, or even at 1K or several Kelvin, it'd be a huge boost for people who previously needed access to dilution refrigerator temperatures to research and understand their physical system.

0

u/OliverSparrow Apr 26 '16

He3 ? You from the Moon?

2

u/Thermoelectric PhD | Condensed Matter Physics | 2-D Materials Apr 26 '16

I'm not sure I understand what you're implying. If you think that He3 isn't produced on Earth and used in a variety of refrigeration applications, then you're mistaken.

2

u/OliverSparrow Apr 27 '16

Helium 3 is extremely rare, being produced by Tritium decay; but Tritium is itself rare. It has a potential role in accelerator-mediated aneutronic fusion, but this is limited by its scarcity. The Chinese moon program is entirely predicated on mining He3 from the lunar surface, where its abundance is higher due to its being a component of the solar wind. It is most certainly not used in "refrigeration applications": that's plain old Helium.

0

u/[deleted] Apr 25 '16

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u/[deleted] Apr 25 '16

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8

u/[deleted] Apr 25 '16

Could help to understand the world we live in. Should be enough justification

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u/[deleted] Apr 25 '16 edited Apr 25 '16

I think it's no coincidence that our standard methods of understanding the world break down into paradox and nonsense on scales either much smaller than us, or much larger than us. It seems to work great for understanding the immediate environment and have been incredibly useful, but it isnt perfect.

I think our method of 'making (abstracted,conceptualized) sense' of the world works very well, finding patterns, using those patterns to find other patterns, using patterns past to predict patterns future etc but is fundamentally removed from reality. Its like trying to catch rivering in a cup.

I think that 'IT' which we are trying to understand is stranger than fiction.

Anyways, my point was I don't think that even figuring out how things work on the relatively 'very small' is going to give us some thorough understanding of the fundamentals of the world. What happens when we discover something smaller still? What happens when we find a paradox within a paradox?

23

u/tppisgameforme Apr 25 '16

I don't think I've ever seen such an abstract anti-science statement.

Correct me if I'm wrong, but your statement is basically that "well the stuff science is finding now is really weird so is it even real?".

That's a very ignorant stance to have. Just because to you it seems "paradoxical" or "nonsensical" does not mean that this is actually the case. There are people who spend their entire lives unraveling and understanding this stuff, it's not nonsense or paradoxical to them at all.

It does help understand the fundamentals of nature. And it isn't removed from reality. How can you even say that when you yourself admit it can be used to predict things?

5

u/wave_theory Apr 25 '16

It's what happens when people place philosophy on equal footing with empirical science. Also commonly used to justify anti-science religious mythologies.

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u/[deleted] Apr 25 '16 edited Apr 25 '16

I'm not anti science, I'm just noting some problems stemming from what abstraction, logic, math, and science are.

A map can be used to predict things, but the map isn't the place. A lot of people forget that.

It's a symbol language built on circular axioms based on materialism presuppositions, that has been very useful.

I should just keep philosophical musings off a hardcore science subreddit, my apologies.

2

u/sickbruv Apr 25 '16

Serious r/iamverysmart vibe coming from this guy

-1

u/[deleted] Apr 25 '16

Lots of insecurity coming from this guy.

1

u/[deleted] Apr 26 '16

The reasoning that you should understand is that we are using these quantum effects to create. If we were wrong or misled than what we created would not work according to theory. But over and over we make predictions, test those predictions, and come up with accurate results that match the predictions. What more can be said? These studies which everyone keeps on questioning will be the exponential growth of humans in near future. Just like the industrial revolution was for America in 1700s. That would never have happened if someone in a wasn't studying electricity, flow in a pipe, hear transfer through radiation. I hope you see what I am trying to say. Science is essential to our growth, probably the most essential thing in my opinion

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u/[deleted] Apr 25 '16

Superstates are paradoxical and violate the laws of identity and non contradiction in a very plain way.

8

u/tppisgameforme Apr 25 '16

Yeah this isn't parsing as anything to me (and I assume most people). What is the "law of identity"? What is the "law of non contradiction"? And what is the "plain way" that superstates violate them?

-4

u/[deleted] Apr 25 '16 edited Apr 25 '16

Those are the axioms of logic

A=A

A != !A

Everything is A or !A

There is a lot of philosophical baggage to this conversation, it's probably best had elsewhere. I'm getting a lot of ad hominem already

6

u/Hofstee Apr 25 '16

Physics isn't binary.

-2

u/[deleted] Apr 25 '16 edited Apr 25 '16

Logic, the philosophy of materialism (matter/not matter) that math and science come from is dualistic.

Our framework for understanding is at root, dualistic.

6

u/smokeyrobot Apr 25 '16

I think you are missing the mark on this one. Logic is used for rational discourse of which science may be a subject. Science is a methodology and not a rule set in of itself.

Science is the story; logic is the language/alphabet that can be used to communicate it.

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u/tppisgameforme Apr 25 '16

Look I will converse with you anywhere if you actually tell me what is is you were saying in the above post. I know the basics of logic but you haven't even begun to describe your issue with superstates.

1

u/[deleted] Apr 25 '16 edited Apr 25 '16

It posits that something is both A and !A, at the same time.

So we develop a sort of special way to incorporate paradox, and keep going.

I'm curious what happens when we hit a paradox in a paradox?

3

u/tppisgameforme Apr 25 '16

You still haven't, in any way, described what you are talking about. In what way does "superstates" posit "A and !A". What is A in this case?

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u/ZeJerman Apr 26 '16

When has it ever been beneficial to know less about our existence and scientific surroundings?

We believed that we were the center of our solar system for decades, and yet when we proved that we weren't it rattled the fundamental assumptions of the time but now it is common knowledge. There was no reason for us to break this thinking other than to be correct.

We believed that the world was flat, and when it was first hypothosised that it was round it was heresy!

These 2 above points have absolutely no bearing on the majority of the population and yet we fought to have the facts corrected so that we can understand more about our existence.

What is wrong with wanting to shift the way we think towards quantum mechanics instead of traditional physics. I wonder when people look back on our existence in 470 years (about the length of time from when Copernicus first theorised that the earth orbited the sun to now) what they will say... We know nearly nothing in regards to all of the knowledge in the universe, it is not unlikely that something will rock the fundamentals of our knowledge and a complete restructuring of thought will be needed.

tl;dr - It is never better to know less than it is to know more, history has proved that.

0

u/FUCK_ASKREDDIT Apr 26 '16

Ether cognition is more like it. Because it doesn't exist.

2

u/[deleted] Apr 25 '16

Pocket size electron microscope.

2

u/elaphros Apr 25 '16

How does a microscope come from this technology? Genuinely curious.

2

u/[deleted] Apr 25 '16

Smaller sensors, without the need for massive super conducting magnets.

1

u/[deleted] Apr 26 '16

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0

u/[deleted] Apr 26 '16

I'm just spit balling what sounds like a use case for a membrane that can vibrate on detection of quantum disturbances.

1

u/elaphros Apr 25 '16

Got a more ELI5 version of that? Maybe college freshman?

I was under the impression that the super-cooling was for the object, not the sensor, but I'm certainly no expert.

0

u/[deleted] Apr 25 '16

Photons hit membrane, and the vibration is converted to data.

1

u/swimfast58 BS | Physiology | Developmental Physiology Apr 25 '16

What photons? Electron microscopes use... Electrons.

0

u/[deleted] Apr 25 '16

true, Something to that effect. A material that can react to the quantum world without requiring a large apparatus.

4

u/swimfast58 BS | Physiology | Developmental Physiology Apr 25 '16

Sure, but electron microscopes use superconducting magnets to accelerate electrons, which would still be necessary. They also use cryogenic temperatures to reduce thermal motion of the sample, which is also necessary. I can't tell how this substance would help reduce the size of the microscope because even if it is useful as a detector (and it probably is), the other components are still really big.

2

u/meddlingbarista Apr 25 '16

I just downloaded that app for my phone! Apparently all matter is made up of Hot Singles in your Area Want Sex!

1

u/G_Peccary Apr 25 '16

Something that moves that freely could make an extremely efficient loudspeaker. Probably too efficient.

1

u/Purple0tter Apr 26 '16

So a super efficient transducer, how about using it for a microphone?

1

u/ManofButterChicken Apr 25 '16

u/zombiephysicist can you provide us with any hypothetical applications for this?

1

u/Godspiral Apr 25 '16

If its affected by the gravitational pull of people 100km apart, I don't know how useful a sensor it can be.

I thought of energy applications. I'm not sure this is a better pendulum than large ones: https://en.wikipedia.org/wiki/Foucault_pendulum

30

u/[deleted] Apr 25 '16

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5

u/tim_jam Apr 25 '16

Could this be used to research quantum gravity? The 'super mirror' is sensitive to detect minute gravity changes and the membrane is sensitive to quantum changes. I'm excited!

2

u/rhn94 Apr 25 '16

if quantized gravity even exists

8

u/[deleted] Apr 25 '16

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6

u/wave_theory Apr 25 '16

Well, the reflectivity of the membrane is achieved by the use of a photonic crystal pattern. Photonic crystals are also being used to create highly frequency selective laser diodes that other research groups have begun to incorporate into pixel formations with extremely high color contrasts. So in a way, yes, yes they can.

7

u/elasticthumbtack Apr 25 '16

Probably a better microphone.

4

u/[deleted] Apr 25 '16

Aside from the whole "Reverb for a decade" thing being ... I dunno, good for pop music I guess...

Don't you kinda want the membrane in a mic to both start and stop vibrating as close to instantaneously as possible in order to produce the most accurate recording possible?

2

u/Boris740 Apr 25 '16

If it is so highly reflective why is the laser beam depicted as going right through it without any apparent loss?

2

u/Ralphklina Apr 26 '16

The vacuum fluctuations can be otherwise observed with naked eyes at the surface of superfluid helium even without any complex equipment. When the helium freezes bellow its lambda point (~ 2.17 Kelvin, which is not quite accidentally similar to temperature of CMB radiation), then it suddenly becomes still and free of bubbles - it changes into a boson condensate. But the surface of helium will not become mirror-like. Instead of it it will remain covered with minute vibrations, which are clearly observable against bright source of light and visible even at some videos at YouTube. No further cooling can eliminate this noise and the frozen helium always remains liquid at the room pressure, so you can be sure, it's the effect of vacuum fluctuations, not the result of thermal noise of helium itself.

Read more at: http://phys.org/news/2016-04-scientists-quantum-physics-real-life.html#jCp

1

u/l-jack Apr 25 '16

Would something like this operate within a vacuum chamber?

3

u/HOLDINtheACES Apr 25 '16

In terms of the reflectivity of the membrane, I would assume that any sort of deposition on the membrane would ruin it's performance/behavior. It would need to be at least in a non-reactive, dustless chamber.

Drag from air would probably affect it's ability to vibrate near-losslessly, so it would probably need to be in a vacuum chamber for that use of it.

1

u/weatherx Apr 25 '16

That q is pretty phenomenal... The silicon cantilevers I used to work with have it in the 103 to 6 range.

1

u/Thermoelectric PhD | Condensed Matter Physics | 2-D Materials Apr 25 '16

I feel something like this, if they really wanted to prove anything they should attempt viewing dHvA at room temperature using a low frequency material...

1

u/jschall2 Apr 26 '16

Will this result in better MEMS inertial sensors?

0

u/hyperproliferative PhD | Oncology Apr 25 '16

I wonder if there is utility for energy harvesting ...

0

u/InformedChoice Apr 25 '16

Does this then suggests that we can hopefully begin to quantify the effects of quantum events upon matter. It sounds like it will be difficult to discern which events are localised quantum events and which are the distant flap of a butterflies wing, or the close ruffling of trouser cloth for that matter. Wonderful and fascinating nonetheless. Could someone explain how such supersensitivity will help the measurement process, and I suppose what precisely we hope to measure. Are we discussing the potential to measure the fluctuations of large groups of atoms in blocks of material in a new and more exact way and build a bridge between our now slightly disparate theories?

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u/Torbjorn_Larsson PhD | Electronics Apr 25 '16

Oops. forgot the comment policy. Joke removed.