Topological phase transition in a topological crystalline insulator induced by finite-size effects

Ozawa, Hideyuki; Yamakage, Ai; Sato, Masatoshi; Tanaka, Yukio

doi:10.1103/physrevb.90.045309

Cited by 53 publications

(61 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, in the normal state, it has been revealed that the edge state of (001) film dramatically changes depending on the number of layers [82]. It can be expected that the similar situation may occur in the superconducting state due to the existence of the steps on the surface.…”

Section: Interpretation Of Experiments and Discussionmentioning

confidence: 88%

Surface electronic state of superconducting topological crystalline insulator

et al. 2015

Self Cite

View full text Add to dashboard Cite

We study the surface state of a doped topological crystalline insulator in the superconducting state. Motivated by Sn1−xInxTe, we consider fully-gapped pair potentials and calculate the surface spectral function. It is found that mirror-protected zero-energy surface Andreev bound states (SABSs) appear at the (001) surface. The gapless points of these SABSs appear on the mirror symmetric line on the surface Brillouin zone while the positions of the gapless points depend on the chemical potential. In addition, due to the presence of the Dirac surface states in the normal state, the dispersion of the SABSs drastically changes with the chemical potential.

show abstract

Section: Interpretation Of Experiments and Discussionmentioning

confidence: 88%

Surface electronic state of superconducting topological crystalline insulator

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…There are many proposed TCI phases depending on different crystal symmetries [4][5][6][7][8][9], yet those relying on mirror symmetry [10] are of particular interest as they have been experimentally observed in, for example, IV-VI semiconductors SnTe, Pb 1−x Sn x Te, and Pb 1−x Sn x Se [11][12][13][14][15]. More materials are theoretically proposed to realize the TCI phases such as rocksalt semiconductors [16,17], pyrochlore iridates [18], graphene systems [19], heavy fermion compounds [20,21], and antiperovskites [22], including two-dimensional (2D) materials such as SnTe thin films [23,24] and a (001) monolayer of PbSe [25].…”

mentioning

confidence: 99%

Layered Topological Crystalline Insulators

et al. 2015

View full text Add to dashboard Cite

Topological crystalline insulators (TCIs) are insulating materials whose topological property relies on generic crystalline symmetries. Based on first-principles calculations, we study a threedimensional (3D) crystal constructed by stacking two-dimensional TCI layers. Depending on the inter-layer interaction, the layered crystal can realize diverse 3D topological phases characterized by two mirror Chern numbers (MCNs) (µ1, µ2) defined on inequivalent mirror-invariant planes in the Brillouin zone. As an example, we demonstrate that new TCI phases can be realized in layered materials such as a PbSe (001) Mirror-symmetric TCIs are mathematically characterized by mirror Chern numbers (MCNs). The MCN is a topological invariant defined by µ 1 ≡ (µ + − µ − )/2 where µ + and µ − are Chern numbers of Bloch states with the opposite eigenvalues of a mirror operator (M z ) calculated on the mirror-invariant plane at k z = 0 in the Brillouin zone (BZ). In a three-dimensional (3D) crystal, there is a second MCN (µ 2 ) defined on the mirror-invariant plane at the boundary of the BZ k z = π (in units of 1/a, where a is the length of the primitive lattice vector along the z-axis) [26]. Moreover, considering different mirror symmetries, multiple pairs of MCNs (µ 1 , µ 2 ) can be simultaneously present in three dimensions. A complete characterization of 3D TCIs requires consideration of all the MCNs, which may allow for the possibility of new states of matter, where MCNs are locked together or undergo separate transitions. Nonetheless, previous study based only on µ 1 has not explored this situation.In this paper, by considering MCNs on all inequivalent mirror-symmetric planes in reciprocal space, we study new topological states of matter realized in a 3D layered crystal generated by stacking 2D TCI layers. We show that the layered system realizes a new class of 3D TCIs when inter-layer interaction is weak, which we will refer to as a layered TCI. The layered TCI is characterized by equal and nonzero first and second MCNs µ 1 = µ 2 = 0 with a number of metallic surface states eqaul to |µ 1 | + |µ 2 |. Increasing the inter-layer interaction, we then show that the layered TCI undergoes topological phase transitions that change the MCNs (µ 1 , µ 2 ). Based on first-principles calculations, we predict that a heterostructure consisting of alternating layers of PbSe monolayer and hexagonal BN (h-BN) sheet realizes the layered TCI indexed by (2,2), and that it undergoes distinct topological phase transitions in the sequence (µ 1 , µ 2 ): (2, 2) → (0, 2) → (0, 0) under external uniaxial tensile strain. Our findings shed light on new states of matter allowed by the presence of multiple MCNs in a 3D crystal. They may also help guide the discovery of more topological materials. Before presenting the results, we first briefly explain arXiv:1503.05966v1 [cond-mat.mtrl-sci]

show abstract

“…Due to the cubic structure in the bulk, electronic structures of IV-VI semiconductor thin films depend crucially on the growth direction [19][20][21][22] . In this work, we study (111) thin films of IV-VI TCIs, which have been grown epitaxially in recent experiments 11,15 .…”

mentioning

confidence: 99%

Electrically tunable quantum spin Hall state in topological crystalline insulator thin films

Liu

2015

Phys. Rev. B

View full text Add to dashboard Cite

Based on electronic structure calculations and theoretical analysis, we predict the (111) thin films of the SnTe class of three-dimensional (3D) topological crystalline insulators (TCIs) realize the quantum spin Hall phase in a wide range of thickness. The nontrivial topology originates from the inter-surface coupling of the topological surface states of TCIs in the 3D limit. The inter-surface coupling changes sign and gives rise to topological phase transitions as a function of film thickness. Furthermore, this coupling can be strongly affected by an external electric field, hence the quantum spin Hall phase can be effectively tuned under the experimentally accessible electric field.

show abstract

Topological phase transition in a topological crystalline insulator induced by finite-size effects

Cited by 53 publications

References 65 publications

Surface electronic state of superconducting topological crystalline insulator

Surface electronic state of superconducting topological crystalline insulator

Layered Topological Crystalline Insulators

Electrically tunable quantum spin Hall state in topological crystalline insulator thin films

Contact Info

Product

Resources

About