Superconductivity emerging upon Se doping of the quantum spin liquid 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>1</mml:mn><mml:mi>T</mml:mi><mml:mtext>−</mml:mtext><mml:msub><mml:mi>TaS</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>

Benedičič, Izidor; Janša, N.; Midden, Marion van; Jeglič, P.; Klanjšek, M.; Zupanič, Erik; Jagličić, Zvonko; Šutar, Petra; Prelovšek, P.; Mihailović, D.; Arčon, Denis

doi:10.1103/physrevb.102.054401

Cited by 6 publications

(5 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In bulk form, 2H-TaS2 is a superconductor with Tc = 0.7 K 18 , while 1T-TaS2 is a correlated insulator 19 with electrons localized on a triangular lattice, predicted to host a quantum spin liquid ground state 20,21 . This suggestion is supported by muon spin relaxation experiments [22][23][24] and nuclear magnetic resonance measurements 23,25 which show an absence of longrange magnetic order. Furthermore, although resistivity clearly shows an insulating behavior, residual specific heat 22,24 and thermal conductivity 26 , and scanning tunneling microscopy measurements 27,28 indicate gapless neutral excitations.…”

mentioning

confidence: 69%

Magnetic memory and spontaneous vortices in a van der Waals superconductor

Persky

Bjørlig

Feldman

et al. 2022

Nature

View full text Add to dashboard Cite

Doped Mott insulators exhibit some of the most intriguing quantum phases of matter, including quantum spin-liquids, unconventional superconductors, and non-Fermi liquid metals [1][2][3] . Such phases often arise when itinerant electrons are close to a Mott insulating state, and thus experience strong spatial correlations 4,5 . Proximity between different layers of van der Waals heterostructures naturally realizes a platform for experimentally studying the relationship between localized, correlated electrons and itinerant electrons. Here, we explore this relationship by studying the magnetic landscape of 4Hb-TaS2, which realizes an alternate stack of a candidate spin liquid and a superconductor 6 . We report on a spontaneous vortex phase whose vortex density can be trained in the normal state. We show that time reversal symmetry is broken above Tc, indicating the presence of a magnetic phase independent of the superconductor. Strikingly, this phase does not generate detectable magnetic signals. We use scanning superconducting quantum interference device (SQUID) microscopy to show that it is incompatible with ferromagnetic ordering. The discovery of this new form of hidden magnetism illustrates how combining superconductivity with a strongly correlated system can lead to new, unexpected physics. Main textIn Van der Waals heterostructures, proximity between layers of different materials can be exploited to generate new states of matter [7][8][9] , or to use one layer in order to probe the properties of the other 10,11 . Indeed, correlated insulating, superconducting, nematic and time-reversal symmetry broken states emerge when uncorrelated electronic systems are stacked together [12][13][14][15][16] . Heterostructures involving strongly correlated systems as their constituents therefore hold promise to realize new phases or find new coupling mechanisms between the layers. A particularly interesting set of ground states to pair is a superconductor and a Mott insulator. Unconventional superconductivity often emerges when a Mott insulator is destroyed by doping 2,3,12 , but how these two phases interact when stacked as individual building blocks remains to be explored. This combination is naturally realized in 4Hb-TaS2, in which two 2D structures of TaS2, octahedral (1T) and trigonal prismatic (2H), are alternatingly stacked 17 . In bulk form, 2H-TaS2 is a superconductor with Tc = 0.7 K 18 , while 1T-TaS2 is a correlated insulator 19 with electrons localized on a triangular lattice, predicted to host a quantum spin liquid ground state 20,21 . This suggestion is supported by muon spin relaxation experiments [22][23][24] and nuclear magnetic resonance measurements 23,25 which show an absence of longrange magnetic order. Furthermore, although resistivity clearly shows an insulating behavior, residual specific heat 22,24 and thermal conductivity 26 , and scanning tunneling microscopy measurements 27,28 indicate gapless neutral excitations. Combined, these results point towards a gapless spin liquid ground state in bulk 1...

show abstract

mentioning

confidence: 69%

Magnetic memory and spontaneous vortices in a van der Waals superconductor

Persky

Bjørlig

Feldman

et al. 2022

Nature

View full text Add to dashboard Cite

show abstract

“…Besides, SC is emerged or enhanced upon isoelectronic Se substitution for Te/S in the parent TMCs (e.g. 1T-PdTe 2 , 1T-TaS 2 , ZrTe 3 ) [27][28][29][30]. The enhancement of T c in 1T-PdSeTe is considered to be arising from the possible existence of metallic Pd or PdTe stripes and/or some dedicated structural disorder caused by a rather small amount of Se deficiency.…”

Section: Introductionmentioning

confidence: 99%

Anomalous charge density wave state evolution and dome-like superconductivity in CuIr₂Te_4−xSe _x chalcogenides

Boubeche¹,

Wang²,

Sun³

et al. 2021

Supercond. Sci. Technol.

View full text Add to dashboard Cite

We report the anomalous charge density wave (CDW) state evolution and dome-like superconductivity in CuIr2Te4−x Se x (0 ⩽ x ⩽ 0.5) series. Room temperature powder x-ray diffraction (XRD) results indicate that CuIr2Te4−x Se x (0 ⩽ x ⩽ 0.5) compounds retain the same structure as the host CuIr2Te4 and the unit cell constants a and c manifest a linear decline with increasing Se content. Magnetization, resistivity and heat capacity results suggest that superconducting transition temperature (T c) exhibits a weak dome-like variation as substituting Te by Se with the maximum T c = 2.83 K for x = 0.1 followed by suppression in T c and simultaneous decrease of the superconducting volume fraction. Unexpectedly, the CDW-like transition (T CDW) is suppressed with lower Se doping (0.025 ⩽ x ⩽ 0.2) but re-emerges at higher doping (0.25 ⩽ x ⩽ 0.5). Meanwhile, the temperature-dependent XRD measurements show that the trigonal structure is stable at 20 K, 100 K and 300 K for the host sample and the doping composition with x = 0.5, thus we propose that the behavior CDW-like transition arises from the disorder effect created by chemical doping and is not related to structural transition. The lower and the upper critical fields of these compounds are also addressed.

show abstract

“…The excellent agreement we obtain with experiment suggests that our simple approach is valid and will be of further use in investigating the rich field of Ta-based CDW and Mott insulator materials; the diversity of CDW behavior in this system has been noted and has certainly not yet been fully explored with complicated hysteretic behavior as a function of temperature, ultrafast dynamics, photodoping, intercalation, alloying and doping for superconductivity, , and monolayer and heterostructure effects all being of current interest. The well-resolved nature of the 4f XPS peaks and their good signal-to-noise makes them a useful probe of the local Ta environment that is accessible in studies of all of the above types.…”

Section: Core Level Shifts Of Charge Density Wave Materialsmentioning

confidence: 58%

First-Principles Estimation of Core Level Shifts for Hf, Ta, W, and Re

et al. 2022

View full text Add to dashboard Cite

A simple first-principles approach is used to estimate the core level shifts observed in X-ray photoelectron spectroscopy for the 4f electrons of Hf, Ta, W, and Re; these elements were selected because their 4f levels are relatively close to the Fermi energy. The approach is first tested by modeling the surface core level shifts of low-index surfaces of the four elemental metals, followed by its application to the well-studied material TaSe 2 in the commensurate charge density wave (CDW) phase, where agreement with experimental data is found to be good, showing that this approach can yield insights into modifications of the CDW. Finally, unterminated surface core level shifts in the hypothetical MXene Ta 3 C 2 are modeled, and the potential of XPS for the investigation of the surface termination of MXenes is demonstrated.

show abstract

Superconductivity emerging upon Se doping of the quantum spin liquid 1T−TaS2

Cited by 6 publications

References 38 publications

Magnetic memory and spontaneous vortices in a van der Waals superconductor

Magnetic memory and spontaneous vortices in a van der Waals superconductor

Anomalous charge density wave state evolution and dome-like superconductivity in CuIr₂Te_4−xSe _x chalcogenides

First-Principles Estimation of Core Level Shifts for Hf, Ta, W, and Re

Contact Info

Product

Resources

About

Superconductivity emerging upon Se doping of the quantum spin liquid 1T−TaS2

Cited by 6 publications

References 38 publications

Magnetic memory and spontaneous vortices in a van der Waals superconductor

Magnetic memory and spontaneous vortices in a van der Waals superconductor

Anomalous charge density wave state evolution and dome-like superconductivity in CuIr2Te4−x Se x chalcogenides

First-Principles Estimation of Core Level Shifts for Hf, Ta, W, and Re

Contact Info

Product

Resources

About

Anomalous charge density wave state evolution and dome-like superconductivity in CuIr₂Te_4−xSe _x chalcogenides