Schoop Lab
@SchoopLab
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We are working on the interface between chemistry and physics, using chemical principles to find new materials with exotic physical properties
Princeton, NJ
Joined January 2019
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This is an attempt of a more coherent thread of why, imo, yesterday's prediction of a flat band at the Fermi level in
#LK99
does not "bring us back" or does resolve the controversy. In short, the prediction assumes the proposed crystal structure is correct, but it might not be.
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Here is a link to our recent findings on
#LK99
together with
@PrincetonPhys
and
@chhendon
, which will appear on arxiv tomorrow. Most important findings are summarized below .
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Finally it is official! Delighted to report that Leslie has been promoted to Associate Professor with tenure effective July first. Obviously this group deserves all the credit. Best lab ever!!! 🎉🥳😊
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Okay I think I need to comment here. It does not surprise me that there is a flatband with the assumed structure. More below. Problem is, is the structure correct? I have doubts. Would like to see phonon calculations to if it’s stable. Can you do this next?
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First phonons out (I would like to see more to me sure). Based on these phonons the crystal structure seems not stable to me, especially in context of the synthesis conditions. I would be extremely cautious about any predictions based on this crystal structure.
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A belated happy new year from the Schoop lab! We start the year with the great news that we have been granted an
@NSF
CAREER grant. Stay tuned for more work on topological square- net materials!
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In a Material where I replace Pb2+ (s0) with Cu2+ (d9) it is very expected that a flat band will appear because what should the lonely d9 electrons do if they are not allowed to magnetize? They will make a flat band. This is why chemically it seems weird this doping is possible
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Hard disagree here. The problem is not a lack in precision of the analysis but a lack in proof that any predicted new material has actually been made. AI could very well made up materials that don’t exist. So far based on the analysis here, proof that these can be made is lacking
Oh boy. This is a great thread to unpack how the experimental world is being held back when thinking about the role of AI/ML. A unfortunately long thread
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Vey excited to join the excellent
@ChemMater
team!
We are also delighted to introduce Prof. Leslie Schoop
@SchoopLab
@PrincetonChem
as the journal's first Topic Editor. Welcome Leslie! Here is the link to her group's website:
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We are excited to share our awesome work on synthesizing a superconducting ink made of 1T-WS2 monolayers, led by
@XiaoyuSong2
! Here we show you can use chemical exfoliation to mass-produce high-quality 2D quantum materials. Also, the ink is stable in air!
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Thank you for providing more data, this is helpful. I have a few questions still that I would love to lean more about:
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It was very nice to collaborate with
@Robert_Palgrave
and students to analyze the autonomous lab paper.Our findings are summarized in the thread here. Most crucial finding imo is that compositional disorder in materials cannot be neglected,as is can lead to incorrect conclusions.
We have now completed our analysis of new materials reported in the Google Deepmind / Berkeley autonomous lab paper. My own initial analysis is in the quote tweet.
Happy to have worked with
@SchoopLab
to jointly put together a comprehensive analysis, now available on
@ChemRxiv
.…
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In the mean time DFT people could do a phonon calculation, which could give us more insight into whether the structure is correct. Imo that would be the easiest next step to check.
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Flat bands usually indicate that our structure is not stable. They could also indicate superconductivity, but only if you are 100% certain that the structure you inputted into the DFT calculation is correct. Very often, seeing flat bands says your structure is wrong.
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This is really nice work from Beijing here about Cu2S, which has a structural phase transition at 385K and can explain the observed resistivity in
#LK99
. It also nice compliments our work.
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We really, really need to be careful with materials characterization. Can’t stress this enough. Excellent thread! ⬇️
This exciting paper shows AI design of materials, robotic synthesis. 10s of new compounds in 17 days.
But did they?
This paper has very serious problems in materials characterisation. In my view it should never have got near publication. Hold on tight let's take a look 😱
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Soooooo happy to be part of this amazing crowd! Thank you
@PackardFdn
for supporting us ❤️
We are excited to announce the 2020
#PackardFellows
in Science and Engineering! Over the next 5 years, these 20
@PackardFdn
Fellows will engage in groundbreaking scientific research and reach new frontiers of discovery. Meet the Fellows: .
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Today, Xiaoyu
@XiaoyuSong2
successfully defended her thesis with an amazing talk about her work on 2D materials. She is the first student from our lab to pass this milestone! Next she will move across the country to work with
@DKBediako
. We are very proud of you!
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So happy to be able to share this news and humbled to be in such great company with this amazing award!
Congrats to Leslie Schoop
@SchoopLab
and Bob Cava, both awarded 5-year, $1.7M
@MooreFound
EPiQS grants. Ready to take on Heisenberg who said, “Not only is the Universe stranger than we think, it is stranger than we can think.”
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1. Samples following the described synthesis are multi-phase
2. Single crystals of an apatite phase can be isolated and are transparent. Our SXRD solution agrees with published powder pattern
3. Cu doping on Pb site seems not feasible based on formation energy calculations
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Happy to share Milena's
@SuperChemGirl
work on chemical rules for kagome materials. We found a tolerance factor that allows to easily predict when they have the typical "kagome bands." We hope it helps many of you finding cool new kagome materials.
@J_A_C_S
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🥰😍❤️
The whole Frick community turned out to support Leslie Schoop for her Friday lecture, “The Chemistry of Quantum Materials.” As Dept Chair Greg Scholes said, “What she���s done since she’s been
@PrincetonChem
is nothing short of extraordinary.”
#WomenInSTEM
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Huge quantum oscillations discovered in a 2D topological insulator! Could this be a sign of neutral fermions? Glad to be part of this work with the Wu lab
@PrincetonPhys
. Awesome for us: Crystal purity strongly enhances the signature :)
@nature
@pccm_mrsec
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Issue with DFT is that crap in crap out so this result entirely relies on the structure being correct. If yes great, if not then it means nothing. So while chemists figure out the structure it might be helpful if DFT people could calculate the phonons and tell us if it’s stable
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After living in 2D square-net works for a long time we have now extended our considerations to 3D. Check out our work on topology in superconducting LaIn3. Nice collaboration with Sam Teicher form UCSB!
@ChemMater
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Check out Mulan's new paper describing how chemical exfoliation can be used to make 1D nanostructures of ionically bound materials. And they can maintain their magnetism during the process! Published in
@nanoscale_rsc
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Very honored to be part of this group and grateful to
@SloanFoundation
for the support.
#SloanFellow
We are pleased to announce the 2021 cohort of the Sloan Research Fellows. These extraordinary early career researchers represent some of the most exciting young minds working today! We are so thrilled to be able to support your work!
#sloanfellow
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So what to next to figure this out? 1. solid-state chemists need to perform a really careful analysis on the material (if you have a floating sample feel free to ship it to us) to really nail down what the crystal structure is, so we have more confidence in the DFT input.
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Here comes the first battery paper from the Schoop lab. Graduate student
@StilesJoseph
(joint with
@CraigArnoldLab
) found that pre-treating NaCrS2 with a mild acid dramatically improves its capacity as a Na-Anode. read the full story at:
#battchat
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Check out Fang's
@FangYua16672278
new paper on atomic resolution imaging of monolayer and twisted bilayer WTe2, together with the Wu group and Princeton's IAC. It wasn't easy to fix samples on a grid, read more to find out what did the trick.
@NanoLetters
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And finally: even if we assume the Cu doped structure to be correct, theory predicts (for the given structure) a magnetic ground state due to localized flat bands.
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Today Robert successfully defended his PhD, being the second graduate from our lab. He was joined with the Scholes lab and gave a great talk on the spectroscopy of materials! His work enabled new areas of research in both labs, he clearly leaves a legacy.Congratulations Dr. Kirby
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Happy to announce that our three second years students all passed their qualifying exams. Congrats to Mulan, Brianna and Scott! 🎉
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Sometimes chemical exfoliation is the superior way for making 2D quantum materials! Grace's paper about the exfoliation of VOCl monolayers appeared today in
@acsnano
. After exfoliation and re-stacking randomly, the magnetic order is maintained.
#womeninSTEM
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Check out our newest paper from
@RatnadwipSingha
and more about an air-stable 2D material with high mobility and probably also magnetism. This follows up on our work on GdTe3, where the air sensitivity is an issue. This is now solved with TaCo2Te2.
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Oh an more good news :)
Leslie Schoop, knocking it out of the park with a
@USNavyResearch
YIP award AND as part of a project team funded by the Schmidt Transformative Tech Fund, both announced within the past few days. Story:
@SchoopLab
#chemistry
#WomeninSTEM
#PrincetonWIC
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Did you know there is a better way to grow superconducting 2M-WS2 as what is currently in the literature? Check out Xiaoyu's
@XiaoyuSong2
and Brianna's paper! (equal contribution) And let us know if you want some high-quality xtals :)
@ChemMater
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We proved a link between delocalized chemical bonds and
#topoligical
band structures! Curious how? Check out Sebastian's new paper , made possible by
@BeckmanFnd
@J_A_C_S
@PrincetonChem
@FlatironCCQ
@mpifkf
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Check out Brianna's work about making thin sheets out of a 3D solid using a clever chemical route. Published in JPhys Materials' focus issue on Women’s Perspective in Quantum Materials.
#WomenInSTEM
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The proposed structure in the original two papers is based on a not very well-performed x-ray analysis.
@Robert_Palgrave
described this better before me. It makes assumptions that are chemically questionable and the chemical reaction is not balanced.
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Very happy to share our most recent paper, where we introduce a new mechanism to design nonsymmorphic topological semimetals. See more here:
with:
@Gvamvim
@AstGroupMPI
@pccm_mrsec
and many more.
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Thus before I put any faith in the proposed structure I would like to see a better x-ray analysis. Together with chemical analysis and more. Now let's get to what this means for the prediction of a flat band.
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@Robert_Palgrave
summarized the chemistry better and I don’t want to repeat it, summary is there are lots of things unclear with the proposed crystal structure
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Black Lives Matter. Racism in science persists to this day, and the diversity crisis in STEM is one symptom of graver and deadlier systemic problems in the US. We as scientists reject the false luxury of remaining silent and urge our peers to act for change in every way possible.
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Let's assume for a sec the structure is correct. In this case Cu2+ was substituted for Pb2+. Those two elements are chemically very different so that would be surprising, but let's for now assume it happened.
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After having studied rare earth tellurides and their Sb doped versions for a while, we now looked at rare earth diantimonides (NdSb2 here) and found that they also are low-dimensional high-mobility magnets. Find out more in
@RatnadwipSingha
's latest paper.
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The lone Cu d electron now does not know what to do. Usually it would try to magnetize. Or find something from the environment to react with. If you model this case with density functional theory (DFT) as was done in the prediction, you will see a flat band.
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Wohooooo we are so proud of our postdoc Milena!!
I am honored to join the amazing chemistry department at NC State University, where I will establish a group focused on theoretical research of quantum materials!
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Awesome story about our recently published new mechanism to design nonsymmorphic Dirac semimetals :)
.
@SchoopLab
publishes on a mechanism to design clean, nonsymmorphic Dirac semimetals, uncovering electronic behaviors that were theorized but not demonstrated. Well done Leslie, Shiming, Kehan, Tyger,
@PrincetonPhys
and collaborators :
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Very happy about this collaborative work, finally proving a prediction I made in graduate school :)
Experimental evidence for the existence of three-dimensional Dirac fermions in Au₂Pb confirms a theoretically predicted Dirac semimetal phase with a fourfold degenerate Dirac crossing protected by rotational lattice symmetry.
#PRL
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Check out Connor’s
@ConnorPollak
first paper in which we show that 1 D electronic properties can exist in a 3D crystal if the 1D motif is surrounded by an electrically inert scaffold. Nice collaboration with
@Gvamvim
@ionerrea
and
@FPielnhofer
Chemical Bonding Induces One-Dimensional Physics in Bulk Crystal BiIr4Se8 | Journal of the American Chemical Society
@SchoopLab
@Princeton
@PrincetonChem
#1D
#Physics
#Bonding
#Crystal
#BiIrSe
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So proud of one of my oldest friends and looking forward to continuing our collaborations! Also everyone please follow
@MuechlerLab
and new grad students or graduating students consider working for this awesome scientist!!
The Penn State Department of Chemistry is pleased to announce that Lukas Muechler will be joining the department faculty as an assistant professor of chemistry! Read more:
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Did you know that a charge density wave can template a magnetic structure? check out Tyger's
@crystal_bubbe
beautiful paper about the connection of a CDW and an elliptical cycloid magnetic structure in NdSbxTe2-x!
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Yesterday’s socially distant outdoor lab party to celebrate Leslie winning the Packard fellowship and to say goodbye to Shiming who is leaving us soon.
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In that case Cu2+, which has 9 d electrons, meaning 1 electron is unpaired, will sit on a site that previously did not have any unpaired electrons (Pb2+ has two electrons in its 6s orbital and no other).
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Wohoooooo! We are proud and happy for our postdoc Jason! Congratulations!🎊🎈🎉🍾
Hi everyone! Starting in August 2023, I’ll begin my independent career at Arizona State University (
@ASU_SMS
) as part of the Navrotsky-Eyring Center for Materials of the Universe. I’m really excited to discover new quantum materials with my group!
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Our perspective with
@Robert_Palgrave
, discussing the challenges of autonomous materials discovery is now published! Check out the final version at
@PRX_Energy
Autonomous materials discovery could rapidly accelerate the development of energy technology. This
#Perspective
from
@SchoopLab
&
@Robert_Palgrave
highlights limitations in the autonomous identification of new materials and identifies current bottlenecks.
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Of course an automatic lab can accelerate accidents but that’s just not as cool as if it finds targeted new predictions. Please prove that part unambiguously!
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I get the argument that the automated lab is not supposed to do everything. But if you make the big claim that you predicted and then synthesized new materials you also need to fully prove that you really made them. I just see now way around that.
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We are happy to share Robert's newest paper, where we investigate the ultrafast dynamics of GdSbxTe2-x, which are CDW-modulated topological semimetals. Rob was a joint student between us and the Scholes group at
@PrincetonChem
, he graduated last summer.
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Nice story about how we contributed to the discovery of the axial Higgs mode by
@Burch_Lab
. A good tale about chemists can have an impact by suggesting the right materials. Solid-state chemistry is so beautiful :)
A 2D quantum material investigated by
@Schooplab
lies at the heart of the discovery of a new quasi-particle announced in Nature, thru a team led by
@BostonCollege
. Congrats Shiming Lei, Leslie Schoop. Story:
#chemistry
#quantum
#MaterialScience
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Check out our newest review about the prospects of chemical exfoliation for 2D quantum materials in
@AppliedPhysRev
:
This was the lockdown project of Xiaoyu (
@XiaoyuSong2
), Fang, and Leslie and also happens to be an all-female author paper.
#WomenInSTEM
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Just accepted: Xiaoyu’s paper about a new layered antiferromagnetic materials and its chemical exfoliation. Read more at: ”
@J_A_C_S
@puprism
@PrincetonIAC
@pccm_mrsec
@PrincetonChem
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Just accepted: Robert's paper on the ultrafast optical spectroscopy of two nodal-line semimetals! Read more at
@PrincetonChem
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No they did not. based on the x-ray analysis there can be side phases. Main phase is an old new material, extra elements can make side phases, which you can see as unfit peaks in the data. There are many very boring explanations for the results that don’t involve new structures
The A-lab found stable structures at previously unexplored compositions. It fit and balanced all structures available in that chemical space and could only determine that a never-before-measured structure was present. Where else did all those other elements go?
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Please read below the really fun story of we found, together with the Wu group, a new way to make 2D materials, where metals form shockingly uniform films on top of TMDs, well below their melting temperature.
Leslie Schoop
@SchoopLab
and Sanfeng Wu
@PrincetonPhys
publish their latest in
@NatureSynthesis
: “Surface-confined two-dimensional mass transport and crystal growth on monolayer materials.” Congratulations Yanyu, Leslie, Sanfeng, and labs!
Story:
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Check out Fang's newest paper where we describe new synthesis routes to make magnetic, Mn-doped SnS2 nanosheets. Our method makes it possible to increase the solubility on Mn4+ in SnS2.
@ChemMater
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Check out Leslie's and Jason's
@JasonKhoury1
new review article in
@TrendsChemistry
! We discuss why chemical bonds matter for topological materials :) Lot's of fun to think about 😊
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Check out our new paper that just appeared in
@PhysRevB
on the signature of an ultrafast photo-induced Lifshitz transition in the topological semimetal ZrSiTe! Read more here:
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Very excited about this work with
@Burch_Lab
. Since our 2020 paper on high mobility in GdTe3 we always knew this material is full of wonders. Now it shows the fist example of an asymmetrical Higgs!
Excited to report our latest
@Nature
discovery of a new particle, the Axial Higgs mode in
#2dmaterial
,
#CDW
via
#Raman
and
#QuantumInterference
… at Room temperature and on the table top. Done with great help from
@SchoopLab
@NarangLab
@BostonCollege
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With postdoc
@NitishMathur19
and a collaboration with
@SongJin_Chem
, the Schoop lab is going 1D! Check out these nanowires that should contain internal Fermi arcs at their twin boundary.
@NanoLetters
Congrats to
@NitishMathur19
on
@NanoLetters
paper with
@SchoopLab
!
These unique nanowires of CoSi
#quantum
material contain merahedral twinning planes & host topological features.
Atomically Sharp Internal Interface in a Chiral Weyl Semimetal Nanowire
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The gender ratio in this picture is depressing. This does not send a good message to young women thinking of going into science. Any plans to address this
@maxplanckpress
?
3 Days and 20 talks later!
Our PhDs and scientists from
@Uni_Stuttgart
,
@uni_ulm
, and
@mpifkf
spent the last 3 days on our online IQST PhD retreat. More than 50 participants overcame the physical distance and enjoyed exciting talks, discussions, and coffee breaks👩🎓☕️🎉
#quantum
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Just out in
@NatureSynthesis
. The formation of a thin metal film on a 2D TMD crystal at temperatures of only ~200 C. Shockingly the film has always 7 metals per TMD formula unit! Fun collaboration with Wu group
@PrincetonPhys
,
@FangYuan_Chem
.
@pccm_mrsec
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Check out our newest work about colossal magneto resistance in a topological semimetal!
Now online
@ScienceAdvances
, our new work from
@SchoopLab
reports a colossal negative magnetoresistance associated with complex cdw state in an antiferromagnetic Dirac semimetal.
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Last month Tyger
@Rock_Salters
passed their generals exam! Today we got to celebrate:) Congratulations to the Schoop lab’s third PhD candidate!! 🎉🎊
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Topological semimetals GdSbxTe2-x exhibit crazy magnetism... See details in our newest paper that just appeared in
@PhysRevB
. We also see a signature that could come from antiferromagnetic skyrmions. Read more here:
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Four years after discovering ZiSiS, we now found topological drumhead surface states in ZrSiTe :) - with Lukas Muechler and Jen Cano
@FlatironCCQ
,
@rpa_queiroz
,
@AstGroupMPI
and more. Check out our work
@PhysRevX
:
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Check out our latest collaboration with Jennifer Cano
@FlatironCCQ
, where we dive into the physics of square-net-based
#topological
semimetals, finding that filling enforced semimetals can exist without nonsymmorphic symmetry.
@PhysRevB
@PrincetonChem
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Here's a group photo from our Labsgiving last week at all-you-can-eat sushi. Happy Thanksgiving from the Schoop lab!
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Great end to 2019! Just accepted: Austin's paper on the synthesis of novel, intrinsically antiferromagnetic nanosheets! Read more at:
@LotschGroup
@InorgChem
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Thank you! How amazing to present the work in from of Roald Hoffmann that is so largely inspired by his old papers!
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We are excited to share that Leslie was selected to be a Beckman Young Investigator! Thanks so much to
@BeckmanFdn
for supporting our research!
#BYI
#BeckmanFoundation
Congratulations to our 2019 Beckman Young Investigators! We’re excited to support these 10 promising young faculty researchers from
@ucla
@dartmouth
@unc
@harvard
@bostoncollege
@caltech
@princeton
@penn
@stanford
READ MORE:
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Cool stuff can happen in extra clean crystals! Check out our latest work in
@PhysRevB
about transport anomalies in high-quality NdTe3 crystals. This work was done with visiting graduate student Kirstine. Congrats Kirstine! Read more at
#WomenInSTEM
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And here is the story, written by our amazing science writer
@wendyplump
about our superconducting ink.
Great new research out today from
@SchoopLab
in
@ScienceAdvances
announcing a simple chemical exfoliation method that produces a high-quality, superconducting nanosheet ink that is stable in air. Congrats Xiaoyu, Ratnadwip and Leslie. Story:
#Chemistry
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❤️❤️❤️ the best part about march meeting!
Weyld girls dinner during MM is also a must.
@roniilan
you were deeply missed.
@SchoopLab
@rpa_queiroz
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Check out Robert's new perspective article on square-net topological semimetals and spectroscopy in the Journal of Physical Chemistry Letters!
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Are those newly predicted materials new structures or just doped versions of Sn2Pb2O7? It seems you predict some oxygen loss. I’m asking because finding new substituted materials is a lot less exciting than new structures.
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Congratulations to our former postdoc Sebastian for winning the attract grant! Sebastian will lead a junior group
@Fraunhofer_IWKS
. We are proud of you!
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Check out this press release about cool new “higher order Fermi arcs” that can appear in semimetals by
@PrincetonPhys
,
@PhysicsIllinois
and more. We were able to contribute to this by looking at the problem from a chemistry perspective :)
@pccm_mrsec
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To end I would like to say it’s cool that robots can make samples. How big of the deal this is, depends on if they actually made something that was predicted BEFORE. Accidental new materials discoveries happen periodically in our lab, I’m sure then also in A-lab.
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Check out Shiming's new paper on an antiferromagnetic metallic van der Waals material in
@ScienceAdvances
!
@PrincetonChem
@PrincetonPhys
@LabYazdani
@AstGroupMPI
@argonne
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Thanks to Tyger for representing our group at the department retreat! Very sad I had to miss her talk, I heard it was spectacular!!! It’s nice to be able to count on everyone in the group 😍
Watching my coworker
@crystal_bubbe
stick the landing at the annual Princeton chemistry department retreat.
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I tried to make a thread and failed. Sorry :( I clearly don’t tweet enough
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Check out Xiaoyu's laters paper on the chemistry behind the synthesis of cdW magnet CrSe2.
@ChemMater
This also marks Leslie's 100th publication 🎉🥳🎉
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