Breakdown of Universal Transport in Correlated<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>d</mml:mi></mml:math>-Wave Superconductors

Andersen, Brian M.; Hirschfeld, P. J.

doi:10.1103/physrevlett.100.257003

Cited by 35 publications

(45 citation statements)

References 42 publications

(45 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…70 Therefore, it would be interesting to compare with quasiparticle interference patterns from more realistic real-space disorder configurations similar to those produced in Refs. [51][52][53][54]56,61,62. The results presented in this paper should be helpful in providing an interpretation of results from future more realistic disorder modeling.…”

Section: Effects Of Disordermentioning

confidence: 85%

Extinction of quasiparticle interference in underdoped cuprates with coexisting order

Andersen

Hirschfeld

2009

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

Recent scanning tunnelling spectroscopy measurements [Y. Koksaka et al., Nature 454, 1072] have shown that dispersing quasiparticle interference peaks in Fourier transformed conductance maps disappear as the bias voltage exceeds a certain threshold corresponding to the coincidence of the contour of constant quasiparticle energy with the antiferromagnetic zone boundary. Here we argue that this is caused by quasistatic short-range coexisting order present in the d-wave superconducting phase, and that the most likely origin of this order is disorder-induced incommensurate antiferromagnetism. We show explicitly how the peaks are extinguished in the related situation with coexisting long-range antiferromagnetic order, and discuss the connection with the realistic disordered case. Since it is the localized quasiparticle interference peaks rather than the underlying antinodal states themselves which are destroyed at a critical bias, our proposal resolves a conflict between scanning tunneling spectroscopy and photoemission regarding the nature of these states.

show abstract

Section: Effects Of Disordermentioning

confidence: 85%

Extinction of quasiparticle interference in underdoped cuprates with coexisting order

Andersen

Hirschfeld

2009

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

show abstract

“…[34] However, for U c1 < U < U c2 magnetic order may be induced in the vicinity of the impurity as shown in Fig. 4(a).…”

Section: Arxiv:13102455v1 [Cond-matsupr-con] 9 Oct 2013mentioning

confidence: 98%

Impurity states and cooperative magnetic order in Fe-based superconductors

2013

Self Cite

View full text Add to dashboard Cite

We study impurity bound states and impurity-induced order in the superconducting state of LiFeAs within a realistic five-band model based on the band structure and impurity potentials obtained from density functional theory (DFT). In agreement with recent experiments, we find that Co impurities are too weak produce sub-gap bound states, whereas stronger impurities like Cu do. We also obtain the bound state spectrum for magnetic impurities, such as Mn, and show how spin-resolved tunnelling may determine the nature of the various defect sites in iron pnictides, a prerequisite for using impurity bound states as a probe of the ground state pairing symmetry. Lastly we show how impurities pin both orbital and magnetic order, providing an explanation for a growing set of experimental evidence for unusual magnetic phases in doped iron pnictides.PACS numbers: 74.70.Xa, 74.62.En, It is crucial to understand the role of disorder in hightemperature superconductors (SC) because the materials are obtained from chemical doping with substitutional impurity atoms. In addition, through the large advance of scanning tunneling microscopy (STM), local perturbations in the host material act as nano-probes of the underlying quantum state. For the Fe-based superconductors (FeSC), a recent series of experiments have measured the local density of states (LDOS) near various impurity sites.[1] In particular, STM measurements within the SC state have focussed largely on FeSe, LiFeAs, and NaFeAs,[2-8] revealing a complex pattern of distinct impurity-induced LDOS modulations including unusual sub-gap bound states, local C 4 symmetry breaking, and generation of electronic dimers. At present no theoretical model exists which correctly captures the LDOS structure near these different impurity sites.Theoretically, both potential and magnetic point-like scatterers can generate in-gap bound states in multi-band s ± -wave SC. The single-impurity problem has been addressed both within simplified two-band models, [9][10][11][12][13][14][15] and a five-band approach, [16] reaching, however, different conclusions about the presence and location of ingap bound states. Recently, an important source of this discrepancy was shown to be the sensitivity of the low-energy states to the band structure and SC gap shape. [17,18] For modelling disorder effects in FeSC, it is therefore crucial to include the correct band structure and minimise the sensitivity of the gap structure by self-consistently calculating the SC gaps arising from this band.A final important recent development is the observation of a component of SDW order observed by e.g. muon spin rotation (µSR) experiments [19][20][21] which "cooperates" with, rather than competes with SC as is commonly assumed. This component, which exists in an intermediate doping range around optimal doping, is evidently correlated with disorder and disappears above T c . This type of disorder-induced magnetism supported by the SC state is reminiscent of that observed in underdoped cuprates where a wedge-like extension...

show abstract

“…[15,16] By contrast, for non-magnetic disorder the s± superconducting state is largely immune to disorder, in agreement with earlier one-band studies, finding that correlations enhance the screening of disorder potentials and thereby reduce pair-breaking and scattering rates compared to the non-interacting case. [17][18][19][20][21] In the current multi-orbital case, however, additional impuritygenerated bound states play an important unexpected role in supporting T c . This resilience to non-magnetic disorder is remarkable since favorable clusters of impurities locally pin magnetic order, eventually causing a volume-full inhomogeneous magnetic state which coexists with superconductivity.…”

mentioning

confidence: 99%

“…How may one understand this result which appears at odds with the expectation that correlations screen disorder and limit their damaging effects? [17][18][19][20][21] The answer to this question necessitates a deeper understanding of correlation effects at both the local scale (immediate vicinity of the impurity sites) and non-local scale (inter-impurity regions). Both effects are intimately tied to the fact that magnetic impurity moments induce spin polarizations of the surrounding itinerant electrons m iµ , which renormalize the exchange coupling such thatH imp =Ĩ iµσ σS iµ c † iµσ c iµσ , wherẽ…”

mentioning

confidence: 99%

Unconventional Disorder Effects in Correlated Superconductors

2016

Self Cite

View full text Add to dashboard Cite

The understanding of disorder has profoundly influenced the development of condensed matter physics, explaining such fundamental effects as, for example, the transition from ballistic to diffusive propagation, and the presence of quantized steps in the quantum Hall effect. For superconductors, the response to disorder reveals crucial information about the internal gap symmetries of the condensate, and thereby the pairing mechanism itself. The destruction of superconductivity by disorder is traditionally described by Abrikosov-Gorkov (AG) theory, [1,2] which however ignores spatial modulations and ceases to be valid when impurities interfere, and interactions become important. Here we study the effects of disorder on unconventional superconductors in the presence of correlations, and explore a completely different disorder paradigm dominated by strong deviations from standard AG theory due to generation of local bound states and cooperative impurity behavior driven by Coulomb interactions. Specifically we explain under which circumstances magnetic disorder acts as a strong poison destroying high-T c superconductivity at the sub-1% level, and when non-magnetic disorder, counter-intuitively, hardly affects the unconventional superconducting state while concomitantly inducing an inhomogeneous full-volume magnetic phase. Recent experimental studies of Fe-based superconductors (FeSC) have discovered that such unusual disorder behavior seem to be indeed present in those systems.For cuprates, heavy-fermions, and FeSC the study of disorder currently constitutes a very active line of research, motivated largely by the fact that these systems are made superconducting by "chemical disordering" (charge doping), but also boosted by controversies of the correct microscopic model, and a rapid development of local experimental probes. [3][4][5] Focusing on multiband FeSC, disorder studies have proven exceptionally rich and strongly material dependent.[6] Scanning tunneling spectroscopy found a plethora of exotic atomicsized impurity-generated states, [7][8][9][10] NMR and neutrons observed clear evidence of glassy magnetic behavior, [11,12] and µSR discovered magnetic phases generated by non-magnetic disorder. [13,14] The resulting complex inhomogeneous phases and their properties in terms of thermodynamics and transport constitute an important open problem in the field.Here, we present a theoretical study of correlationdriven emergent impurity behavior of both magnetic and nonmagnetic disorder in unconventional s± multi-band superconductors. For the case of magnetic disorder, we find that correlations anti-screen the local moment, and significantly enhance the inter-impurity RudermanKittel-Kasuya-Yosida (RKKY) exchange interactions by inducing non-local long-range magnetic order which operates as an additional competitor to superconductivity. This results in an aggressive T c suppression rate where superconductivity is wiped out by sub-1% concentrations of disorder. This mechanism explains the "poisoning effect" discovered in ...

show abstract

Breakdown of Universal Transport in Correlatedd-Wave Superconductors

Cited by 35 publications

References 42 publications

Extinction of quasiparticle interference in underdoped cuprates with coexisting order

Extinction of quasiparticle interference in underdoped cuprates with coexisting order

Impurity states and cooperative magnetic order in Fe-based superconductors

Unconventional Disorder Effects in Correlated Superconductors

Contact Info

Product

Resources

About