RKKY interaction of magnetic impurities in Dirac and Weyl semimetals

Chang, Hao-Ran; Zhou, Jinhong; Wang, Shixiong; Shan, Wen-Yu; Xiao, Di

doi:10.1103/physrevb.92.241103

Cited by 124 publications

(128 citation statements)

References 59 publications

Supporting

Mentioning

112

Contrasting

Unclassified

Order By: Relevance

“…The Kondo problem is an important issue in condensed matter physics and has been widely studied by using various methods [15][16][17][18][19][20][21][22][23] . The Kondo problem as well as the RKKY interactions in systems with isotropic Dirac cones have been studied intensively since the discoveries of graphene and topological insulators [24][25][26][27] . At half- * sunjinhua@nbu.edu.cn † donghuixu@hubu.edu.cn filling, the density of states (DOS) of the Dirac fermions vanishes, and the problem of a magnetic impurity in such systems falls into the category of pseudo-gap Kondo problem [28][29][30] .…”

Section: Topological Semimetalsmentioning

confidence: 99%

Single magnetic impurity in tilted Dirac surface states

Sun

Wang

et al. 2018

Phys. Rev. B

View full text Add to dashboard Cite

We utilize variational method to investigate the Kondo screening of a spin-1/2 magnetic impurity in tilted Dirac surface states with the Dirac cone tilted along the ky-axis. We mainly study about the effect of the tilting term on the binding energy and the spin-spin correlation between magnetic impurity and conduction electrons. The binding energy has a critical value while the Dirac cone is slightly tilted. However, as the tilting term increases, the density of states near the Dirac node becomes significant, such that the impurity and the host material always favor a bound state. The diagonal and the off-diagonal terms of the spin-spin correlation between the magnetic impurity and conduction electrons are also studied. Due to the spin-orbit coupling and the tilting of the spectra, various components of spin-spin correlation show very strong anisotropy in coordinate space, and are of power-law decay with respect to the spatial displacements.

show abstract

Section: Topological Semimetalsmentioning

confidence: 99%

Single magnetic impurity in tilted Dirac surface states

Sun

Wang

et al. 2018

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…This complication did not arise in Refs. 31,32. In the present paper we are going to investigate the indirect spin exchange coupling J eff (R) between two dopants residing directly above carbon atoms of intrinsic graphene.…”

Section: Introductionmentioning

confidence: 99%

Long-range exchange interaction between magnetic impurities in graphene

Agarwal

Mishchenko

2017

Phys. Rev. B

View full text Add to dashboard Cite

The effective spin exchange coupling between impurities (adatoms) on graphene mediated by conduction electrons is studied as a function of the strength of the potential part of the on-site energy U of the electron-adatom interaction. With increasing U , the exchange coupling becomes long-range, determined largely by the impurity levels with energies close to the Dirac points. When adatoms reside on opposite sublattices, their exchange coupling, normally antiferromagnetic, becomes ferromagnetic and resonantly enhanced at a specific distance where an impurity level crosses the Dirac point.

show abstract

“…An external magnetic field or magnetic doping can implement the breaking of the time-reversal symmetry. A few theoretical studies have predicted a Ruderman-Kittel-Kasuya-Yosida interaction and a Kondo effect among the magnetic impurities in both Dirac and Weyl semimetals [34][35][36][37], although the experimental evidence remains lacking.…”

Section: Introductionmentioning

confidence: 99%

Cr doping induced negative transverse magnetoresistance in Cd3As2 thin films

et al. 2018

View full text Add to dashboard Cite

The magnetoresistance of a material conveys various dynamic information about charge and spin carriers, inspiring both fundamental studies in physics and practical applications such as magnetic sensors, data storage, and spintronic devices. Magnetic impurities play a crucial role in the magnetoresistance as they induce exotic states of matter such as the quantum anomalous Hall effect in topological insulators and tunable ferromagnetic phases in dilute magnetic semiconductors. However, magnetically doped topological Dirac semimetals are hitherto lacking. Here, we report a systematic study of Cr-doped Cd 3 As 2 thin films grown by molecular-beam epitaxy. With the Cr doping, Cd 3 As 2 thin films exhibit unexpected negative transverse magnetoresistance and strong quantum oscillations, bearing a trivial Berry's phase and an enhanced effective mass. More importantly, with ionic gating the magnetoresistance of Cr-doped Cd 3 As 2 thin films can be drastically tuned from negative to positive, demonstrating the strong correlation between electrons and the localized spins of the Cr impurities, which we interpret through the formation of magnetic polarons. Such a negative magnetoresistance under perpendicular magnetic field and its gate tunability have not been observed previously in the Dirac semimetal Cd 3 As 2 . The Cr-induced topological phase transition and the formation of magnetic polarons in Cd 3 As 2 provide insights into the magnetic interaction in Dirac semimetals as well as their potential applications in spintronics.

show abstract

RKKY interaction of magnetic impurities in Dirac and Weyl semimetals

Cited by 124 publications

References 59 publications

Single magnetic impurity in tilted Dirac surface states

Single magnetic impurity in tilted Dirac surface states

Long-range exchange interaction between magnetic impurities in graphene

Cr doping induced negative transverse magnetoresistance in Cd3As2 thin films

Contact Info

Product

Resources

About