Band bending and alignment at the spinel/perovskite<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>γ</mml:mi><mml:mtext>−</mml:mtext><mml:msub><mml:mtext>Al</mml:mtext><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mtext>O</mml:mtext><mml:mn>3</mml:mn></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mtext>SrTiO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math>heterointerface

Schütz, P.; Pfaff, Florian; Scheiderer, Philipp; Chen, Yunzhong; Pryds, Nini; Gorgoi, Mihaela; Sing, M.; Claessen, R.

doi:10.1103/physrevb.91.165118

Cited by 36 publications

(32 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The conductivity of the AlO/STO heterostructures used in this work is in good agreement with the previous reports 10,32,[37][38][39] , as shown in Sup- with a crystal field gap as large as ∼ 2 eV in the octahedral symmetry 9,[13][14][15][16][17][18] . Additionally, the strong spin-orbit interaction induces the splitting of the Ti 2p core level into 2p 1/2 and 2p 3/2 states.…”

Section: Resultssupporting

confidence: 92%

See 1 more Smart Citation

Anomalous orbital structure in a spinel–perovskite interface

et al. 2016

View full text Add to dashboard Cite

In all archetypical reported (001)-oriented perovskite heterostructures, it has been deduced that the preferential occupation of two-dimensional electron gases is in-plane dxy state. In sharp contrast to this, the investigated electronic structure of a spinel-perovskite heterostructure γ-Al2O3/SrTiO3 by resonant soft X-ray linear dichroism, demonstrates that the preferential occupation is out-of-plane dxz/dyz states for interfacial electrons. Moreover, the impact of strain further corroborates that this anomalous orbital structure can be linked to the altered crystal field at the interface and symmetry breaking of the interfacial structural units. Our findings provide another interesting route to engineer emergent quantum states with deterministic orbital symmetry.

show abstract

Section: Resultssupporting

confidence: 92%

“…may be present at AlO/STO interfaces 37 . The conductivity of the AlO/STO heterostructures used in this work is in good agreement with the previous reports 10,32,[37][38][39] , as shown in Sup- with a crystal field gap as large as ∼ 2 eV in the octahedral symmetry 9,[13][14][15][16][17][18] .…”

Section: Resultsmentioning

confidence: 99%

Anomalous orbital structure in a spinel–perovskite interface

et al. 2016

View full text Add to dashboard Cite

show abstract

“…From our results, we are forced to conclude that the potential barrier of the valence bands at the interface between the STO and Al 2 O 3 region is relatively small, whereas there is a large potential barrier for the conduction bands. Similar band diagram has been proposed recently by the density functional calculations 7 and by the hard x-ray photoelectron spectroscopy 35 , but it has not been addressed in the 2DEG system formed by amorphous Al 2 O 3 layer. In this configuration, the photogenerated electrons cannot easily penetrate into the metal electrodes due to the large potential barriers.…”

Section: Resultssupporting

confidence: 52%

“…However, this is improbable because the Al 2 O 3 surface is known to capture the hole carriers instead. In the following results, we found that the photocurrent polarity can be successfully interpreted in terms of a new band alignment picture, in which the hole carriers in the valence band are collected by the electrodes while the electrons in the conduction band are blocked by the high potential barrier of the Al 2 O 3 layer 34, 35 .…”

Section: Resultsmentioning

confidence: 83%

Electronic Band Alignment at Complex Oxide Interfaces Measured by Scanning Photocurrent Microscopy

Yoon

Jung

Hong

et al. 2017

Sci Rep

View full text Add to dashboard Cite

The band alignment at an Al2O3/SrTiO3 heterointerface forming a two-dimensional electron gas (2DEG) was investigated using scanning photocurrent microscopy (SPCM) in an electrolyte-gated environment. We used a focused UV laser source for above-the-bandgap illumination on the SrTiO3 layer, creating electron-hole pairs that contributed to the photocurrent through migration towards the metal electrodes. The polarity of the SPCM signals of a bare SrTiO3 device shows typical p-type behavior at zero gate bias, in which the photogenerated electrons are collected by the electrodes. In contrast, the SPCM polarity of 2DEG device indicates that the hole carriers were collected by the metal electrodes. Careful transport measurements revealed that the gate-dependent conductance of the 2DEG devices exhibits n-type switching behavior. More importantly, the SPCM signals in 2DEG devices demonstrated very unique gate-responses that cannot be found in conventional semiconducting devices, based on which we were able to perform detailed investigation into the electronic band alignment of the 2DEG devices and obtain the valence band offset at the heterointerface.

show abstract

“…Rashba-type SOC not only depends on n s [3] but also on the electric field at the interface [48] and hence polarity of the heterostructure. For the epitaxial grown spinel-type/perovskite heterostructure γ-Al 2 O 3 /STO the polar character and potential buildup is expected to be comparable to that of LAO/STO or even larger [49]. A low deposition temperature T s , as used here, indeed leads to a strongly disordered and quasi amorphous structure of Al 2 O 3 .…”

Section: A Temperature Dependence Of the Electronic Transportmentioning

confidence: 74%

Anisotropic electronic transport of the two-dimensional electron system in Al2O3/SrTiO3 heterostructures

et al. 2017

View full text Add to dashboard Cite

Transport measurements on the two-dimensional electron system in Al 2 O 3 /SrTiO 3 heterostructures indicate significant non-crystalline anisotropic behavior below T ≈ 30 K.Lattice dislocations in SrTiO 3 and interfacial steps are suggested to be the main sources for electronic anisotropy. Anisotropic defect scattering likewise alters magnetoresistance at low temperature remarkably and influences spin-orbit coupling significantly by the Elliot-Yafet mechanism of spin relaxation resulting in anisotropic weak localization. Applying a magnetic field parallel to the interface results in an additional field-induced anisotropy of the conductance, which can be attributed to Rashba spin-orbit interaction. Compared to LaAlO 3 /SrTiO 3 , Rashba coupling seems to be reduced indicating a weaker polarity in Al 2 O 3 /SrTiO 3 heterostructures.

show abstract

Band bending and alignment at the spinel/perovskiteγ−Al2O3/SrTiO3heterointerface

Cited by 36 publications

References 52 publications

Anomalous orbital structure in a spinel–perovskite interface

Anomalous orbital structure in a spinel–perovskite interface

Electronic Band Alignment at Complex Oxide Interfaces Measured by Scanning Photocurrent Microscopy

Anisotropic electronic transport of the two-dimensional electron system in Al2O3/SrTiO3 heterostructures

Contact Info

Product

Resources

About