Polarization-Driven Topological Insulator Transition in a<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>GaN</mml:mi><mml:mo>/</mml:mo><mml:mi>InN</mml:mi><mml:mo>/</mml:mo><mml:mi>GaN</mml:mi></mml:math>Quantum Well

Miao, Maosheng; Yan, Qimin; Walle, Chris G. Van de; Lou, Wenkai; Li, L. L.; Chang, Kai

doi:10.1103/physrevlett.109.186803

Cited by 162 publications

(127 citation statements)

References 32 publications

Supporting

Mentioning

108

Contrasting

Order By: Relevance

“…Very recently, a new way to exploring topological insulating phase in semiconductors was proposed utilizing strong piezoelectric effect at the interface between GaN and InN. [22] The strain between these material results in a huge polarization and electric field cross the interfaces. This huge electric field not only can invert the conduction and valence bands, but also generate strong Rashba SOI, eventually drive the system into topological insulating phase.…”

mentioning

confidence: 99%

Interface-Induced Topological Insulator Transition inGaAs/Ge/GaAsQuantum Wells

Zhang¹,

Lou²,

Miao³

et al. 2013

Phys. Rev. Lett.

138

View full text Add to dashboard Cite

We demonstrate theoretically that interface engineering can drive Germanium, one of the most commonly-used semiconductors, into topological insulating phase. Utilizing giant electric fields generated by charge accumulation at GaAs/Ge/GaAs opposite semiconductor interfaces and band folding, the new design can reduce the sizable gap in Ge and induce large spin-orbit interaction, which lead to a topological insulator transition. Our work provides a new method on realizing TI in commonly-used semiconductors and suggests a promising approach to integrate it in well developed semiconductor electronic devices.PACS numbers: 71.70. Ej, 75.76.+j, 72.25.Mk Time-reversal invariant topological insulators (TIs) have aroused intensive interests in the past years, with tantalizing properties such as insulating bulk, robust metallic edge or surface modes and exotic topological excitations, and potential applications ranging from spintronics to quantum computation. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] Despite these successful progresses, the topological insulator materials are still limited in the narrow gap materials containing heavy atoms, e.g., HgTe, [4,5] Bi 2 X 3 (X=Se, Te,...) [8][9][10][11], transition metal oxide heterostructure [16] and Heusler compounds [12,17]. These materials are often very different from conventional semiconductor materials in structures and properties and are hard to be integrated in current electronics devices that are based on well developed semiconductor fabrication technologies.Although there are theoretical predicts about realizing TI states in graphene, [3,18,19] the main obstacle is the weak intrinsic spin-orbit interaction (SOI) of carbon atoms. Here, instead of searching new TI materials with exotic structures and chemical elements, we take a totally different route: driving the commonly used semiconductors into TI states by using the intrinsic electric field and the strains. The difficulty of this approach lies in the fact that most of the commonly used semiconductors, such as Si, Ge, GaAs and many others usually possess sizable band gaps and do not have strong enough SOI. Furthermore, group IV elements such as Si and Ge have indirect band gap, posing extra difficulty in realizing TI. Inspired by recent theoretical works that the normal insulator [20] can be driven into a TI by an external electric field, our approach is to impose huge electric field by deliberately designed heterostructures. Recently, an interesting way of realizing topological insulating phase in a p-type GaAs quantum well by two-dimentional superimposed potentials with hexagonal symmetry was proposed.[21] Different to that work, our approach rely completely on the material engineering at the atomic level.Since commonly-used semiconductors, e.g., Si, Ge, GaAs, posses sizable bandgap ranging from 0.8eV to 1.4eV, a huge electric field is required to closing bandgap and even invert the conduction and valence bands. Such huge electric field can not be generated utilizing the gate technique. However, recent ...

show abstract

mentioning

confidence: 99%

Interface-Induced Topological Insulator Transition inGaAs/Ge/GaAsQuantum Wells

Zhang¹,

Lou²,

Miao³

et al. 2013

Phys. Rev. Lett.

138

View full text Add to dashboard Cite

show abstract

“…The band structure parameters for this Hamiltonian have been obtained by interpolating the literature data for GaN and InN from Refs. [2] and [3]. In order to take into account the broken translational symmetry in the direction perpendicular to the QW plane, the z-component of momentum in the Hamiltonian is replaced by the −i ∂ ∂z operator.…”

Section: Theoretical Modelmentioning

confidence: 99%

“…To overcome this problem ultrathin InN/GaN quantum wells (QWs) and superlattices have been considered [1]. It has been shown theoretically by means of the ab initio calculations that in these structures grown along c crystalline axis, the energy gap at the Γ point of the Brillouin zone changes dramatically with the QW width from about 2 eV for 1 monolayer (ML) of InN to 0 eV, with inverted order of the conduction and valence band states, for 34 MLs of InN [2]. This eect is associated with the presence of the built-in electric elds originating from the spontaneous and piezoelectric polarizations.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Polarization-Induced Band Inversion in In-Rich InGaN/GaN Quantum Wells

2014

View full text Add to dashboard Cite

We theoretically study the polarization-induced band inversion phenomenon in c-plane In-rich InGaN/GaN quantum wells. Our calculations performed using the k · p method with the 8 × 8 RashbaShekaPikus Hamiltonian for the structures with the indium content between 90% and 100% show that the reordering of the conduction and valence bands occurs for the quantum well widths below the theoretical values of critical thickness for InGaN layers pseudomorphically grown on GaN substrates.

show abstract

“…These heterostructures can potentially host exotic electronic states: for example, the strong mixing of the electron and hole states across the InN layer in Fig 1(c), combined with the very high electric field-induced Rashba effect causes an effective band-inversion -as highlighted by the broken gap alignment. In these structures, topological edge-states are predicted to occur [18]. The search for such exotic electronic states of matter offer strong motivation to address the significant challenges in realizing these heterostructures in the future.…”

mentioning

confidence: 99%

Polarization-induced Zener tunnel diodes in GaN/InGaN/GaN heterojunctions

Yan

Islam

et al. 2015

Applied Physics Letters

View full text Add to dashboard Cite

By the insertion of thin InxGa1−xN layers into Nitrogen-polar GaN p-n junctions, polarizationinduced Zener tunnel junctions are studied. The reverse-bias interband Zener tunneling current is found to be weakly temperature dependent, as opposed to the strongly temperature-dependent forward bias current. This indicates tunneling as the primary reverse-bias current transport mechanism. The Indium composition in the InGaN layer is systematically varied to demonstrate the increase in the interband tunneling current. Comparing the experimentally measured tunneling currents to a model helps identify the specific challenges in potentially taking such junctions towards nitride-based polarization-induced tunneling field-effect transistors.

show abstract

Polarization-Driven Topological Insulator Transition in aGaN/InN/GaNQuantum Well

Cited by 162 publications

References 32 publications

Interface-Induced Topological Insulator Transition inGaAs/Ge/GaAsQuantum Wells

Interface-Induced Topological Insulator Transition inGaAs/Ge/GaAsQuantum Wells

Polarization-Induced Band Inversion in In-Rich InGaN/GaN Quantum Wells

Polarization-induced Zener tunnel diodes in GaN/InGaN/GaN heterojunctions

Contact Info

Product

Resources

About