Device creates negative mass—and a novel way to generate lasers

January 10, 2018, University of Rochester
In this optical microcavity, created by the lab of Nick Vamivakas, confined light interacts with an atomically thin semiconductor to create particles with negative mass. The device also presents “a way to generate laser light with an incrementally small amount of power,” says Vamivakas, an associate professor of quantum optics and quantum physics at Rochester’s Institute of Optics. Credit: Michael Osadciw/University of Rochester

Most objects react in predictable ways when force is applied to them—unless they have "negative mass." And then they react exactly opposite from what you would expect.

Now University of Rochester researchers have succeeded in creating particles with negative in an atomically thin semiconductor, by causing it to interact with confined light in an optical microcavity.

This alone is "interesting and exciting from a physics perspective," says Nick Vamivakas, an associate professor of quantum optics and quantum physics at Rochester's Institute of Optics. "But it also turns out the device we've created presents a way to generate laser light with an incrementally small amount of power."

The device, described in Nature Physics, consists of two mirrors that create an optical microcavity, which confines light at different colors of the spectrum depending on how the mirrors are spaced.

Researchers in Vamivakas' lab, including co-lead authors Sajal Dhara (now with the Indian Institute of Technology) and Ph.D. student Chitraleema Chakraborty, embedded an atomically thin molybdenum diselenide semiconductor in the microcavity.

The semiconductor was placed in such a way that its interaction with the confined light resulted in small particles from the —called excitons—combining with photons from the confined to form polaritons.

"By causing an exciton to give up some of its identity to a photon to create a , we end up with an object that has a negative mass associated with it," Vamivakas explains. "That's kind of a mind-bending thing to think about, because if you try to push or pull it, it will go in the opposite direction from what your intuition would tell you."

Other research groups have been experimenting with similar devices, Vamivakas says, but this is the first device to produce particles with negative mass.

Though applications are "still down the road," Vamivakas adds, his lab will continue to explore:

  • How the device might serve as a substrate for producing lasers. "With the polaritons we've created with this device, the prescription for getting a to operate is completely different," Vamivakas says. "The system starts lasing at a much lower energy input" than traditional lasers now in use.
  • The physical implications of creating negative mass in the device. "We're dreaming up ways to apply pushes and pulls—maybe by applying an electrical field across the device—and then studying how these polaritons move around in the under application of external force."

Explore further: Defects in atomically thin semiconductor emit single photons

More information: S. Dhara et al. Anomalous dispersion of microcavity trion-polaritons, Nature Physics (2017). DOI: 10.1038/nphys4303

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31 comments

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TheGhostofOtto1923
5 / 5 (1) Jan 10, 2018
So if you had a space ship with a negative mass you could put the engine on the front and use it to deflect dust?
÷)
ellbeeyoo
1 / 5 (2) Jan 10, 2018
Negative mass??? I think not. Negative mass has an equivalent negative energy and such a thing, while theoretically possible, has never been seen and most believe that the energies needed to create negative energy are well beyond human ability to achieve.
The hypothetical Warp drive requires negative energy and the reason we don't have warp drives is that it has been found impossible to create negative energy. If it were this easy to create 'negative' mass/energy we would have a warp drive in no time, and I bet everything I have that doesn't happen.
antialias_physorg
5 / 5 (6) Jan 10, 2018
Negative mass has an equivalent negative energy and such a thing, while theoretically possible, has never been seen

They are talking about a quasiparticle (a polariton) which behaves *as if* it has negative mass. Note that these are of the boson type.

Negative mass??? I think not.

What you are thinking about are fermions (stuff made up of quarks like protons and neutrons or leptons like electrons). The quasiparticles in the article are are not fermions.
DarkLordKelvin
3.8 / 5 (4) Jan 10, 2018
*sigh* .. why do otherwise intelligent physicists get caught up in the need to make outlandish, obviously unphysical claims? They did not create an entity that actually possesses "negative mass". They created configurations of energy states within a material that CAN BE CHARACTERIZED as a quasiparticle; there is no requirement that we think of it as a particle-like entity, it's just convenient from certain respects. In turn that quasiparticle behaves, in at least some respects, as if it were a particle with "negative mass", although from the sound of things, "negative inertia" would be a more accurate description of the phenomena they actually observed.
xponen
4.8 / 5 (4) Jan 10, 2018
Caution: nobody should take the weird named particles with "negative mass" literally... it is just waves (like ripple on a string) in solid material that solid-state physicist/fan label as "particle".

for example: polariton, exciton or plasmon... is just a ripples made by atoms in crystals or ripples made by electrons in metal that had cool names... it's like calling the mexican waves in a stadium full of soccer fan as "human-iton particles" .

more detail can be found in solid state physic textbook.

do not get fooled by these stupid naming.
xponen
5 / 5 (2) Jan 10, 2018
it's just like that thing: "positive charge flowing in a circuit".... it's just an idea/model not what literally happen.
Da Schneib
not rated yet Jan 10, 2018
This is not really negative mass. Polaritons don't have mass, negative or otherwise.
Mimath224
4.5 / 5 (2) Jan 10, 2018
@Da Schneib In addition to what you say I'm not sure that a 'push or pull' as described above would count as a definition of negative mass. I do understand that there are many possible 'attributes' that neg m might display, though I hasten to add that I haven't gone into any real detail when reading about neg m. It would seem to me that before one starts using meg m terminology one would need to examine the impact on KE, SR, GR etc. In other words, would I be correct in suggesting that using 'neg m' as in the article is perhaps premature?
Da Schneib
5 / 5 (3) Jan 11, 2018
@Mimath, more like nonexistent. And I mean experimentally. What these guys are saying is that it acts as if it had negative mass, if it had mass and acted like things that have mass do. Which it doesn't.
Mimath224
not rated yet Jan 11, 2018
@Da Schneib Thanks for the reply..understood. Do you know of reasonable experimental papers on neg m on the net as I'd like to know a bit more? Thanks in advance.
Da Schneib
5 / 5 (1) Jan 11, 2018
@Mimath, the only results I know about that indicate "negative mass" are in articles here on PhysOrg, and they're all about quasiparticles, not about real massive particles with negative mass. As I said this is not really negative mass.
SwamiOnTheMountain
1 / 5 (1) Jan 11, 2018
Yeah they really glossed over the whole "negative mass" thing. haha.
Some would say that is as impossible as dividing by zero.
rrwillsj
1 / 5 (3) Jan 11, 2018
My suspicions (unverified) is that this research team is in a toxic environment of extreme competition for funding.

As they say in Show Business "Even bad publicity is better than NO publicity!"

I have worked in business and academic institutions, where the guy approving the funding? All too often turns out to be a sadistic bastard. Who did not really understand the research beneath his raptor wings. Or even care about the success or failure of a project. He will take all the credit for success. And never accept any share of blame for failures. That's what subordinates are for!

In the desperate struggle for recognition, researchers are grasping at straws to get a good count of eyeballs for their publications. Because, all too often that is how their superiors measure success.
milnik
1 / 5 (1) Jan 14, 2018
Negative mass creates negative and weird consciousness. First, I see that none of you are trying to get away from it: WHAT IS MATERIAL? What are the basic ingredients of matter, and the mass is a bunch of matter. Are well-paid fools know what a laser is and how it shares on matter and its constituents.
If the quark, as the basis of matter, is negative, what makes him a negative one? There is no negative matter in the universe, only it can be particles in which an electron is inserted into force (a neutron with an inserted electron, but it is not a stable particle). If you insert an electron into a proton, you get a neutron. Do you know what is happening in a neutron with an electron-positron pair?
milnik
3 / 5 (2) Jan 14, 2018
THE SCIENCE IS UNKNOWN. To understand this, I would not fool and pretend to know everything about what is magnetism, and in fact there are completely "hollow" brains. Are you interested in how matter arises and disappears, from what is formed and into what is being dissolved? It's not nature so stupid that it complicates the birth of a phenomenon, as the "scientists" see it. And what are the delusions? And that's the natural law !! Whoever does not want to accept the structure of the universe and who does not know and does not recognize the existence of the Spiritual Entity of the Universe (SEU), is spiritually blind and crazy in understanding it.
milnik
2.3 / 5 (3) Jan 14, 2018
@mackita,
I thought you were trying to figure it out and that you really understood what matter, time and space were. Einstein gave you all the pill for "the curvature of the time an adversary) and therefore you have a completely curved understanding of everything that is" clear to you ".
Accept free AETHER pill, and there is only one enough, and it will be clear to you that you have been trembling to this day. How do you not understand that Aether is a fixed substance with electromagnetic properties and that light can not move without Aether, because light also has electromagnetic properties. These are "relatives" such as Aether cousin with gluons (magnetism) and with quarks, electrons, positrons (gravity). Organize a seminar to direct the entire science to the right path, because you have gone astray into some "dark" spaces.
milnik
3 / 5 (2) Jan 15, 2018
@mackita,
I see that you are worse than a carpenter, who does not believe in anything, only in something that is so ordered to him. You have realized that I'm turning Eether into a religion. That means you do not know what religion is and what is Aether, how will you know when you are not connected, consciously or intuitively with the Spiritual entity of the universe. What you think I do not have evidence, you are mistaken, and you do not know that my country and my country were robbed and destroyed by types that do not believe in anything, but only in fatamorganes. ETHER is what you call "dark", only it is neither matter nor energy, but substance at the border of matter and spiritual entity.
milnik
2.3 / 5 (3) Jan 15, 2018
Because of the idiots who have filled the science of Aether with the whole universe, and those idiots look at themselves, and if someone wants to make something useful, they ask for it to pay for it. I do not have the money because, but I have enough paper to leave it all out for some time, when tycoon idiots will disappear and honest people will see that value.
And something else, to educate you: I establish a connection with Aether using a small magnet and a copper wire spool and I get electricity from whatever you call it.
It does not need any movement, no wire or magnet. I can understand what AETHER is, and he has understood who I am, but one day you will understand it, when you throw out quantum mechanics, Einstein's and Lorenz's nonsense from the head, and those around BB.
ellbeeyoo
2.3 / 5 (3) Jan 15, 2018
@mackita
The EM drive does not work by creating 'negative mass'. It supposedly uses another method that is equally forbidden by physics. NASA has NOT said that it works. Some people in the business claims that it works on a scale in micronewtons and to scale it up to a useful quantity would also be impossible. If NASA though that the thing worked we would be hearing about it every day, yet we hard a few releases and then nothing. It has not been proven to work and if it does work it cannot be scaled up to useful quantities of energy.
ellbeeyoo
1 / 5 (1) Jan 15, 2018
"Extraordinary claims require extraordinary evidence" was a phrase made popular by Carl Sagan and it applies here. Someone here who does know more than I do pointed out that they aren't talking about fermions, but some type of particle that behave AS IF it had negative mass. I have to point out that AS IF means it isn't negative mass, but has some characteristics that could be called negative mass-like. There is a great deal of difference between appearing as something and actually being something. They claim to achieve negative mass; the laws of physics say NO it just looks that way.
savvys84
1 / 5 (2) Jan 15, 2018
Lol negative mass?
This is gonna fizzle out for sure
antialias_physorg
not rated yet Jan 15, 2018
Lol negative mass?
This is gonna fizzle out for sure

You didn't really bother to read the article, did you?
Bongstar420
not rated yet Jan 15, 2018
Are we sure the best thing we can think up for this is laser guns and inertial stabilizers?
Osiris1
1 / 5 (1) Jan 15, 2018
Great science. Let the idiot naysayers rave as that is what they do best..... like heathens. Negative mass is the key to negative energy as well. Easy to make lasers mean more tech yet. Negative energy means at least low intensity Alcubierre fields, which at first will not be warp drives per se, but could be very fast moving ships indeed in their own small bubble of sub warp inertial reference frame. Think trips to Proxima Centauri's planets in less than two years.... and back. Such a lure of a new home for man will gain followers.... such will literally come out of the woodwork. Man's journey to his birthright has begun.
savvys84
1 / 5 (4) Jan 16, 2018
Lol negative mass?
This is gonna fizzle out for sure

You didn't really bother to read the article, did you?

Says who?
And I already have an anti gravity device.
chk out https://www.scrib...savvys84
milnik
2.3 / 5 (3) Jan 16, 2018
Only a maniac can claim and know what anti-gravity is, if it does not know what gravity is. Suluda is also a claim with the light of the bends when passing by the heavens with great gravity. It means they do not even know what light is, and especially what gravity is. If we can overcome the gravitational force by some other force, that does not mean that we have found antigravity.
When people understand and study the causes of the motion of the material particles, and also the celestial bodies, then the intelligentsia will be the mutual effect of magnetism and gravity through AETHER. Many arouse the story of Aether, but let it be so, because they will get used to like gravity, although they do not know what it is and how it arises.
savvys84
1 / 5 (2) Jan 17, 2018
@mackita

Thanks for all your comments. and since there is a paucity of comments, would welcome you to comment on youtube https://www.youtu...g68VE-Ys

Lol I would be a us citizen in God's eyes since I became a Born Again Christian there
milnik
not rated yet Jan 17, 2018
@mackita,
I will try to analyze everything that has been said about Sage theory, although I also see that none of this explanation is in line with nature. If there are so many participants in the solution to the problem of gravity, and there is no solution, what does that mean for conscious people?
You mention transversal waves, and who formed them and through which substance can they move? You say it is not clear. You say that virtual bosons: photons, gluons, Hi gz particles and to shorten the time, and some scalar field and space heating. These are all nebuloses. It comes out as if there is a new entity of the universe and your listed "guests" come as strangers and uninvited tourists to interfere with the work of these waves. What is a virtual part for you?
milnik
1 / 5 (1) Jan 17, 2018
Who formed it? In the science there are so many false and fictitious phenomena that poor gravity will escape from the universe, and we will not know why it was present in the universe. I'm more and more convinced that I'm right, because you have countless Fatamorgana.
Imagine that the Spiritual entity of the universe is watching you, and it is not easy for him to appear those who formed him, nor do they know him or acknowledge him.
milnik
1 / 5 (2) Jan 17, 2018
It's time to accept my evidence, because all the previous theories fall into the water, and everything is so simple for me, so those who are accustomed to complicated formulas, false models, wrong theories, are hard to get used to the simplicity that nature has determined. Only those who do not know the cause of the phenomenon have more evidence. But, remember, there is only one truth about the cause of the phenomenon, and the false ones have as many as there are those who want to get rich from lies, at the expense of nature and those who speak the truth. WONDERFUL: GLUON IS A VIRTUAL PARTICLE. If there is no gluon, there would be no magnetism. !!!
milnik
1 / 5 (2) Jan 17, 2018
@mackita,
and electron and positron and gluons are formed by Aether, but in a series of thermodynamic processes, in the presence of the base-AETHER, quarks, gluons, especially chemical elements, gases, clouds of gases, masses, celestial bodies (magnetists, double-pulsars, neutron stars), and when they explode as supernovae, the stars form like the sun and with them the planet and other mass graves. These contaminating stories of the expansion of the universe, the galaxies, and the Hubble constant do not correspond to the universe. And galaxies have their center of gravity around which they move, but science does not see that Kepler's laws need to be corrected, because the true path of heavenly bodies does not appear from it. I corrected those laws and came to understand what spin, photon, wave, and much more.

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