Landau level spectroscopy of valence bands in HgTe quantum wells: effects of symmetry lowering

The Landau level spectroscopy technique has been used to explore the electronic structure of the valence band in a series of p-type HgTe/HgCdTe quantum wells with both normal and inverted ordering of bands. We find that the standard axial-symmetric 4-band Kane model, which is nowadays widely applied in physics of HgTe-based topological materials, does not fully account for the complex magneto-optical response observed in our experiments—notably, for the unexpected avoided crossings of excitations and for the appearance of transitions that are electric-dipole forbidden within this model. Nevertheless, reasonable agreement with experiments is achieved when the standard model is expanded to include effects of bulk and interface inversion asymmetries. These remove the axial symmetry, and among other, profoundly modify the shape of valence bands.

[1]  V. Gavrilenko,et al.  Stimulated emission from HgCdTe quantum well heterostructures at wavelengths up to 19.5 μm , 2017 .

[2]  A. A. Sherstobitov,et al.  Valence band energy spectrum of HgTe quantum wells with an inverted band structure , 2017, 1705.04717.

[3]  J. Torres,et al.  Temperature-driven single-valley Dirac fermions in HgTe quantum wells , 2017, 1702.06869.

[4]  M. Scherr,et al.  Photogalvanic probing of helical edge channels in 2D HgTe topological insulators , 2016, 1612.08854.

[5]  Z. Kvon,et al.  Universal Faraday Rotation in HgTe Wells with Critical Thickness. , 2016, Physical review letters.

[6]  L. Molenkamp,et al.  Strain Engineering of the Band Gap of HgTe Quantum Wells Using Superlattice Virtual Substrates. , 2016, Physical review letters.

[7]  W. Knap,et al.  Phase transitions in two tunnel-coupled HgTe quantum wells: Bilayer graphene analogy and beyond , 2016, Scientific Reports.

[8]  G. V. Astakhov,et al.  Observation of the universal magnetoelectric effect in a 3D topological insulator , 2016, Nature Communications.

[9]  V. Gavrilenko,et al.  Long wavelength stimulated emission up to 9.5 μm from HgCdTe quantum well heterostructures , 2016 .

[10]  M. Durnev,et al.  Magnetic field effects on edge and bulk states in topological insulators based on HgTe/CdHgTe quantum wells with strong natural interface inversion asymmetry , 2015, 1512.05312.

[11]  A. A. Sherstobitov,et al.  Spin-orbit splitting of valence and conduction bands in HgTe quantum wells near the Dirac point , 2015, 1511.06506.

[12]  W. Knap,et al.  Anticrossing of Landau levels in HgTe/CdHgTe (013) quantum wells with an inverted band structure , 2015 .

[13]  B. McCombe,et al.  Landau levels and spin splitting in the two-dimensional electron gas of a HgTe quantum well near the critical width for the topological phase transition , 2014 .

[14]  A. Zunger,et al.  Split Dirac cones in HgTe/CdTe quantum wells due to symmetry-enforced level anticrossing at interfaces , 2014, 1411.1910.

[15]  A. A. Sherstobitov,et al.  Hole transport and valence-band dispersion law in a HgTe quantum well with a normal energy spectrum , 2014, 1402.1316.

[16]  X. G. Wu,et al.  Influence of bulk inversion asymmetry on the magneto-optical spectrum of a HgTe topological insulator , 2013, 1309.5557.

[17]  J. Torres,et al.  Magnetospectroscopy of two-dimensional HgTe-based topological insulators around the critical thickness , 2012 .

[18]  W. Knap,et al.  Cyclotron resonance in HgTe/CdTe-based heterostructures in high magnetic fields , 2012, Nanoscale Research Letters.

[19]  V. Gavrilenko,et al.  Cyclotron resonance in HgTe/CdTe(013) narrowband heterostructures in quantized magnetic fields , 2012 .

[20]  M. Goiran,et al.  Cyclotron resonance and interband optical transitions in HgTe/CdTe(0 1 3) quantum well heterostructures , 2011 .

[21]  L. Molenkamp,et al.  Fine structure of zero-mode Landau levels in HgTe/HgxCd1−xTe quantum wells , 2010, 1011.5233.

[22]  L. Molenkamp,et al.  Single valley Dirac fermions in zero-gap HgTe quantum wells , 2010, 1009.2248.

[23]  V. Gavrilenko,et al.  Spin splitting in HgTe/CdHgTe (013) quantum well heterostructures , 2010 .

[24]  Yu. G. Sidorov,et al.  Growth of HgTe Quantum Wells for IR to THz Detectors , 2010 .

[25]  L. Molenkamp,et al.  Quantum Spin Hall Insulator State in HgTe Quantum Wells , 2007, Science.

[26]  Shou-Cheng Zhang,et al.  Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells , 2006, Science.

[27]  Yu. G. Sidorov,et al.  Growth of Hg1-xCdxTe nanostructures by molecular beam epitaxy with ellipsometric control , 2006 .

[28]  L. Molenkamp,et al.  Band structure of semimagnetic Hg 1 − y Mn y Te quantum wells , 2004, cond-mat/0409392.

[29]  L. Molenkamp,et al.  Giant spin-orbit splitting in a HgTe quantum well , 2004, cond-mat/0406518.

[30]  C. Becker,et al.  Effectivegfactor ofn-typeHgTe/Hg1−xCdxTesingle quantum wells , 2004 .

[31]  C. Becker,et al.  Absence of magneto-intersubband scattering in n-type HgTe quantum wells , 2002 .

[32]  C. Becker,et al.  Rashba splitting in n-type modulation-doped HgTe quantum wells with an inverted band structure , 2001 .

[33]  C. Becker,et al.  Quantum transport in n-type and p-type modulation-doped mercury telluride quantum wells , 2000 .

[34]  R. Winkler,et al.  Crossing of conduction- and valence-subband Landau levels in an inverted HgTe/CdTe quantum well , 1998 .

[35]  T. Skauli,et al.  Rashba spin splitting in a gated HgTe quantum well , 1996 .

[36]  C. Becker,et al.  Landau-split and spin-split cyclotron resonance of two-dimensional electron systems in HgTe quantum wells , 1996 .

[37]  R. Ranvaud,et al.  Quantum resonances in the valence band of zinc-blende semiconductors. II. Results for p -InSb under uniaxial stress , 1979 .

[38]  Ronald Ranvaud,et al.  Quantum resonances in the valence bands of zinc-blende semiconductors. I. Theoretical aspects , 1979 .

[39]  K. Suzuki,et al.  Quantum resonances in the valence bands of germanium. II. Cyclotron resonances in uniaxially stressed crystals , 1974 .

[40]  J. Hensel,et al.  Quantum resonances in the valence bands of germanium. I. Theoretical considerations , 1974 .

[41]  C. Becker,et al.  Effective g factor of n-type HgTe'Hg 1¿x Cd x Te single quantum wells , 2004 .

[42]  R. Winkler.  Inversion-Asymmetry-Induced Spin Splitting , 2003 .