Magnetoresistance in Degenerate CdS: Localized Magnetic Moments

Khosla, Rajinder P.; Fischer, Joachim

doi:10.1103/physrevb.2.4084

Cited by 206 publications

(167 citation statements)

References 39 publications

Supporting

Mentioning

151

Contrasting

Order By: Relevance

“…Many references exist in the literature pointing out the negative magnetoresistance of impurity band conduction, but typical values are at most a few percent. 31 We recall here that negative longitudinal magnetoresistances of comparable size were found in transport measurements in LAO/STO interfaces and attributed to the low-temperature antiferromagnetic state of the LAO/STO interface. 23 However, those samples did not show the positive low-temperature contribution to magnetoresistance, suggesting that the origin may be different.…”

mentioning

confidence: 99%

“…The large values found here suggest a magnetic origin as reported for semiconductors doped with paramagnetic transition metal ions. 31 The scattering of conduction electrons by localized moments is known to yield a negative magnetoresistance term scaling as the magnetization squared 32,33 due to the coupling of spin and momentum through the spin-orbit interaction. A spin-flip process results in momentum reversal due to the strong coupling between spins and momenta and consequently contributes to the resistivity.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Anisotropic magnetotransport in SrTiO3surface electron gases generated by Ar+irradiation

et al. 2011

View full text Add to dashboard Cite

Metallic surface layers are fabricated by doping (100) SrTiO 3 (STO) single crystals with oxygen vacancies generated by bombardment with Ar ions from an rf plasma source. The presence of oxygen vacancies is confirmed by cathodoluminescence and x-ray photoemission spectroscopy. This technique produces a surface electron gas with high values of the sheet carrier density (n 2D = 2.45×10 17 cm −2 ). A strong increase (300%) of the low-temperature magnetoresistance is observed when the magnetic field is rotated away from the surface, characteristic of orbital effects of confined electrons. We estimate the width of the confinement region to be in the 200-300 nm range. When a magnetic field is applied in the surface plane and parallel to the current direction, a large negative magnetoresistance is found below the structural transition of the STO, which is discussed in terms of spin-orbit scattering. On further reduction of temperature, there is a change to a positive magnetoresistance regime due to the scattering of charge carriers at the disordered surface region.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Anisotropic magnetotransport in SrTiO3surface electron gases generated by Ar+irradiation

et al. 2011

View full text Add to dashboard Cite

show abstract

“…This general behavior of the crystalline state is in sharp contrast to the conduction properties of a number of heavily doped semiconductors where one observes a negative magnetoresistance. There are many different models [9][10][11][12][13][14][15][16] in the literature trying to explain this anomalous behavior. They are all related to a model by Toyozawa [17] where the conduction electrons scatter against localized spins.…”

Section: Introductionmentioning

confidence: 99%

Magnetoresistance of doped silicon

et al. 2015

View full text Add to dashboard Cite

We have performed longitudinal magnetoresistance measurements on heavily n-doped silicon for donor concentrations exceeding the critical value for the metal-nonmetal transition. The results are compared to those from a many-body theory where the donor electrons are assumed to reside at the bottom of the many-valley conduction band of the host. Good qualitative agreement between theory and experiment is obtained.

show abstract

“…The absence of hysteresis (supplementary information) at these fields indicates this is not a first order transition such as ferromagnetism. At positive density the MR is smooth and we fit the MR to the Khosla-Fischer expression for spin-flip scattering by local moments [27]:…”

mentioning

confidence: 99%

Rashba Interaction and Local Magnetic Moments in a Graphene-BN Heterostructure Intercalated with Au

et al. 2016

View full text Add to dashboard Cite

We intercalate a van der Waals heterostructure of graphene and hexagonal Boron Nitride with Au, by encapsulation, and show that Au at the interface is two dimensional. A charge transfer upon current annealing indicates redistribution of Au and induces splitting of the graphene bandstructure. The effect of in plane magnetic field confirms that splitting is due to spin-splitting and that spin polarization is in the plane, characteristic of a Rashba interaction with magnitude approximately 25 meV. Consistent with the presence of intrinsic interfacial electric field we show that the splitting can be enhanced by an applied displacement field in dual gated samples. Giant negative magnetoresistance, up to 75%, and a field induced anomalous Hall effect at magnetic fields < 1 T are observed. These demonstrate that hybridized Au has a magnetic moment and suggests the proximity to formation of a collective magnetic phase. These effects persist close to room temperature.Spin orbit coupling in graphene is induced by hybridization with heavy metals [1]. This has been achieved by intercalation of graphene using e.g. Au, which produces a Rashba interaction ∼ 100 meV [2], and Pb [3], on metallic substrates. We intercalate Au into a heterostructure of graphene and dielectric hexagonal Boron Nitride (hBN), and report spin-splitting of the graphene bands observed in quantum oscillations on an insulating substrate, a crucial requirement for applications. The Rashba interaction is large (25 meV) for samples intercalated with 0.1 monolayers (ML) of Au, but is modulated by modest electric fields, thereby highlighting the requirement of hybridization with spin-split Au d-electrons [2]. We observe large negative magnetoresistance, up to 75%, indicating Au ions form magnetic moments and an anomalous Hall effect suggests the possible formation of a collective magnetic phase. The combination of Rashba interaction, magnetic moments and electric field control of the density, is akin to dilute magnetic semiconductors [4], and in a Dirac material opens a route toward electric field control of magnetism and engineering topological magnetic states such as the quantum anomalous Hall effect [5,6].The van der Waals interaction can create an atomically clean interface between stacked two-dimensional (2D) crystals [7]; therefore, it can be considered organizing principle for atoms or molecules at a hetero-interface [8]. Here, we use the van der Waals interaction to cleanly intercalate Au between graphene and hBN and to induce strong hybridization between graphene and Au. We intercalate graphene-hBN heterostructures by depositing 0.1-0.5 nominal ML of Au onto freshly cleaved hBN on SiO 2 in ultra high vacuum. Au decorated hBN is used as the substrate onto which a separately prepared graphene/hBN (thickness ≈ 20 nm) is transferred, the structure is illustrated in Fig. 1a. The stack is etched and metallic contacts are formed at the exposed edges of graphene [9]. Following thermal annealing the heterostructure is flat with root mean square roughness of 0....

show abstract

Magnetoresistance in Degenerate CdS: Localized Magnetic Moments

Cited by 206 publications

References 39 publications

Anisotropic magnetotransport in SrTiO3surface electron gases generated by Ar+irradiation

Anisotropic magnetotransport in SrTiO3surface electron gases generated by Ar+irradiation

Magnetoresistance of doped silicon

Rashba Interaction and Local Magnetic Moments in a Graphene-BN Heterostructure Intercalated with Au

Contact Info

Product

Resources

About