1932

Abstract

Two-dimensional electron gases (2DEGs) at oxide interfaces may exhibit unique properties, including effects from strong electron correlations, extremely high electron densities, magnetism, and 2D superconductivity. This article discusses routes to high-mobility 2DEGs in complex oxide heterostructures, with a particular focus on 2DEGs that involve transport in SrTiO. We discuss what is known about the electronic states in SrTiO 2DEGs, both experimentally and theoretically. Examples from the current literature are summarized.

Loading

Article metrics loading...

/content/journals/10.1146/annurev-matsci-070813-113552
2014-07-01
2024-06-19
Loading full text...

Full text loading...

/deliver/fulltext/matsci/44/1/annurev-matsci-070813-113552.html?itemId=/content/journals/10.1146/annurev-matsci-070813-113552&mimeType=html&fmt=ahah

Literature Cited

  1. Tsui DC, Stormer HL, Gossard AC. 1.  1982. Two-dimensional magnetotransport in the extreme quantum limit. Phys. Rev. Lett. 48:1559–62 [Google Scholar]
  2. Pfeiffer L, West KW. 2.  2003. The role of MBE in recent quantum Hall effect physics discoveries. Physics E 20:57–64 [Google Scholar]
  3. Jena D.3.  2008. Polarization effects on low-field transport & mobility in III–V nitride HEMTs. Polarization Effects in Semiconductors C Wood, D Jena 161–216 New York: Springer [Google Scholar]
  4. Singh J.4.  2003. Electronic and Optoelectronic Properties of Semiconductor Structures Cambridge, UK: Cambridge Univ. Press [Google Scholar]
  5. Tsukazaki A, Ohtomo A, Kita T, Ohno Y, Ohno H, Kawasaki M. 5.  2007. Quantum Hall effect in polar oxide heterostructures. Science 315:1388–91 [Google Scholar]
  6. Tsukazaki A, Akasaka S, Nakahara K, Ohno Y, Ohno H. 6.  et al. 2010. Observation of the fractional quantum Hall effect in an oxide. Nat. Mater. 9:889–93 [Google Scholar]
  7. van der Marel D, van Mechelen JLM, Mazin II. 7.  2011. Common Fermi-liquid origin of T2 resistivity and superconductivity in n-type SrTiO3. Phys. Rev. B 84:205111 [Google Scholar]
  8. Frederikse HPR, Hosler WR. 8.  1967. Hall mobility in SrTiO3. Phys. Rev. 161:822–27 [Google Scholar]
  9. Cox PA.9.  1992. Transition Metal Oxides Oxford, UK: Clarendon [Google Scholar]
  10. Mott NF.10.  1949. The basis of the electron theory of metals, with special reference to the transition metals. Proc. Phys. Soc. A 62:416–22 [Google Scholar]
  11. Imada M, Fujimori A, Tokura Y. 11.  1998. Metal-insulator transitions. Rev. Mod. Phys. 70:1039–263 [Google Scholar]
  12. Bhattacharya A, May S. 12.  2014. Magnetic oxide heterostructures. Annu. Rev. Mater. Res. 44: 65–90 [Google Scholar]
  13. Ngai JH, Walker FJ, Ahn CH. 13.  2014. Correlated oxide physics and electronics. Annu. Rev. Mater. Res. 44: 1–17 [Google Scholar]
  14. Mannhart J, Blank DHA, Hwang HY, Millis AJ, Triscone J-M. 14.  2008. Two-dimensional electron gases at oxide interfaces. MRS Bull. 33:1027–34 [Google Scholar]
  15. Mannhart J, Schlom DG. 15.  2010. Oxide interfaces: an opportunity for electronics. Science 327:1607–11 [Google Scholar]
  16. Huijben M, Brinkman A, Koster G, Rijnders G, Hilgenkamp H, Blank DHA. 16.  2009. Structure-property relation of SrTiO3/LaAlO3 interfaces. Adv. Mater. 21:1665–77 [Google Scholar]
  17. Zubko P, Gariglio S, Gabay M, Ghosez P, Triscone J-M. 17.  2011. Interface physics in complex oxide heterostructures. Annu. Rev. Condens. Matter Phys. 2:141–65 [Google Scholar]
  18. Schlom DG, Haeni JH, Lettieri J, Theis CD, Tian W. 18.  et al. 2001. Oxide nano-engineering using MBE. Mater. Sci. Eng. B 87:282–91 [Google Scholar]
  19. Schlom DG, Chen LQ, Pan XQ, Schmehl A, Zurbuchen MA. 19.  2008. A thin film approach to engineering functionality into oxides. J. Am. Ceram. Soc. 91:2429–54 [Google Scholar]
  20. Dingle R, Stormer HL, Gossard AC, Wiegmann W. 20.  1978. Electron mobilities in modulation-doped semiconductor heterojunction superlattices. Appl. Phys. Lett. 33:665–67 [Google Scholar]
  21. Eisenstein JP, Cooper KB, Pfeiffer LN, West KW. 21.  2002. Insulating and fractional quantum Hall states in the first excited Landau level. Phys. Rev. Lett. 88:076801 [Google Scholar]
  22. Umansky V, Heiblum M, Levinson Y, Smet J, Nubler J, Dolev M. 22.  2009. MBE growth of ultra-low disorder 2DEG with mobility exceeding 35 × 106 cm2/V s. J. Cryst. Growth 311:1658–61 [Google Scholar]
  23. Mimura T, Hiyamizu S, Fujii T, Nanbu K. 23.  1980. A new field-effect transistor with selectively doped GaAs/n-AlxGa1−xAs heterojunctions. Jpn. J. Appl. Phys. 19:L225–27 [Google Scholar]
  24. Delagebeaudeuf D, Linh NT. 24.  1982. Metal-(n) AlGaAs-GaAs two-dimensional electron gas FET. IEEE Trans. Electron. Devices 29:955–60 [Google Scholar]
  25. Zunger A, Kilic C, Wang L. 25.  2002. Defects in photovoltaic materials and the origin of failure to dope them. Proc. IEEE Photovoltaic Spec. Conf., 29th, New Orleans 2002 500–3 [Google Scholar]
  26. van Benthem K, Elsässer C, French RH. 26.  2001. Bulk electronic structure of SrTiO3: experiment and theory. J. Appl. Phys. 90:6156–64 [Google Scholar]
  27. Lim SG, Kriventsov S, Jackson TN, Haeni JH, Schlom DG. 27.  et al. 2002. Dielectric functions and optical bandgaps of high-K dielectrics for metal-oxide-semiconductor field-effect transistors by far ultraviolet spectroscopic ellipsometry. J. Appl. Phys. 91:4500–5 [Google Scholar]
  28. Derks C, Kuepper K, Raekers M, Postnikov AV, Uecker R. 28.  et al. 2012. Band-gap variation in RScO3 (R = Pr, Nd, Sm, Eu, Gd, Tb, and Dy): X-ray absorption and O K-edge X-ray emission spectroscopies. Phys. Rev. B 86:155124 [Google Scholar]
  29. Lee YS, Lee JS, Noh TW, Byun DY, Yoo KS. 29.  et al. 2003. Systematic trends in the electronic structure parameters of the 4d transition-metal oxides SrMO3(M = Zr, Mo, Ru, and Rh). Phys. Rev. B 67:113101 [Google Scholar]
  30. Schafranek R, Baniecki JD, Ishii M, Kotaka Y, Yamanka K, Kurihara K. 30.  2012. Band offsets at the epitaxial SrTiO3/SrZrO3 (0 0 1) heterojunction. J. Phys. D 45:055303 [Google Scholar]
  31. Janotti A, Bjaalie L, Gordon L, Van de Walle CG. 31.  2012. Controlling the density of the two-dimensional electron gas at the SrTiO3/LaAlO3 interface. Phys. Rev. B 86:241108 [Google Scholar]
  32. Berner G, Müller A, Pfaff F, Walde J, Richter C. 32.  et al. 2013. Band alignment in LaAlO3/SrTiO3 oxide heterostructures inferred from hard X-ray photoelectron spectroscopy. Phys. Rev. B 88:115111 [Google Scholar]
  33. Chambers SA, Engelhard MH, Shutthanandan V, Zhu Z, Droubay TC. 33.  et al. 2010. Instability, intermixing and electronic structure at the epitaxial LaAlO3/SrTiO3 heterojunction. Surf. Sci. Rep. 65:317–52 [Google Scholar]
  34. Delugas P, Filippetti A, Gadaleta A, Pallecchi I, Marré D, Fiorentini V. 34.  2013. Large band offset as driving force of two-dimensional electron confinement: the case of SrTiO3/SrZrO3 interface. Phys. Rev. B 88:115304 [Google Scholar]
  35. Kajdos AP, Ouellette DG, Cain TA, Stemmer S. 35.  2013. Two-dimensional electron gas in a modulation-doped SrTiO3/Sr(Ti, Zr)O3 heterostructure. Appl. Phys. Lett. 103:082120 [Google Scholar]
  36. Schooley JF, Hosler WR, Cohen ML. 36.  1964. Superconductivity in semiconducting SrTiO3. Phys. Rev. Lett. 12:474–75 [Google Scholar]
  37. Lin X, Zhu ZW, Fauque B, Behnia K. 37.  2013. Fermi surface of the most dilute superconductor. Phys. Rev. X 3:021002 [Google Scholar]
  38. Ambacher O, Smart J, Shealy JR, Weimann NG, Chu K. 38.  et al. 1999. Two-dimensional electron gases induced by spontaneous and piezoelectric polarization charges in N- and Ga-face AlGaN/GaN heterostructures. J. Appl. Phys. 85:3222–33 [Google Scholar]
  39. Ibbetson JP, Fini PT, Ness KD, DenBaars SP, Speck JS, Mishra UK. 39.  2000. Polarization effects, surface states, and the source of electrons in AlGaN/GaN heterostructure field effect transistors. Appl. Phys. Lett. 77:250–52 [Google Scholar]
  40. Speck JS, Chichibu SF. 40.  2009. Nonpolar and semipolar group III nitride-based materials. MRS Bull. 34:304–9 [Google Scholar]
  41. Ahn CH, Bhattacharya A, Di Ventra M, Eckstein JN, Frisbie CD. 41.  et al. 2006. Electrostatic modification of novel materials. Rev. Mod. Phys. 78:1185–212 [Google Scholar]
  42. Ahn CH, Gariglio S, Paruch P, Tybell T, Antognazza L, Triscone J-M. 42.  1999. Electrostatic modulation of superconductivity in ultrathin GdBa2Cu3O7−x films. Science 284:1152–55 [Google Scholar]
  43. Wu YR, Singh J. 43.  2005. Polar heterostructure for multifunction devices: theoretical studies. IEEE Trans. Electron. Devices 52:284–93 [Google Scholar]
  44. Hoffman J, Pan XA, Reiner JW, Walker FJ, Han JP. 44.  et al. 2010. Ferroelectric field effect transistors for memory applications. Adv. Mater. 22:2957–61 [Google Scholar]
  45. Harrison WA, Kraut EA, Waldrop JR, Grant RW. 45.  1978. Polar heterojunction interfaces. Phys. Rev. B 18:4402–10 [Google Scholar]
  46. Ohtomo A, Hwang HY. 46.  2004. A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface. Nature 427:423–26 [Google Scholar]
  47. Nakagawa N, Hwang HY, Muller DA. 47.  2006. Why some interfaces cannot be sharp. Nat. Mater. 5:204–9 [Google Scholar]
  48. Stengel M.48.  2011. First-principles modeling of electrostatically doped perovskite systems. Phys. Rev. Lett. 106:136803 [Google Scholar]
  49. Stengel M.49.  2011. Electrostatic stability of insulating surfaces: theory and applications. Phys. Rev. B 84:205432 [Google Scholar]
  50. Bristowe NC, Ghosez P, Littlewood PB, Artacho E. 50.  2013. Origin of two-dimensional electron gases at oxide interfaces: insights from theory. arXiv:1310.8427 [cond-mat.mes-hall]
  51. Crandles DA, Timusk T, Garrett JD, Greedan JE. 51.  1992. The mid infrared absorption in RTiO3 perovskites (R = La, Ce, Pr, Nd, Sm, Gd): the Hubbard gap?. Physica C 201:407–12 [Google Scholar]
  52. Kim JS, Seo SSA, Chisholm MF, Kremer RK, Habermeier HU. 52.  et al. 2010. Nonlinear Hall effect and multichannel conduction in LaTiO3/SrTiO3 superlattices. Phys. Rev. B 82:201407 [Google Scholar]
  53. Moetakef P, Cain TA, Ouellette DG, Zhang JY, Klenov DO. 53.  et al. 2011. Electrostatic carrier doping of GdTiO3/SrTiO3 interfaces. Appl. Phys. Lett. 99:232116 [Google Scholar]
  54. Cain TA, Moetakef P, Jackson CA, Stemmer S. 54.  2012. Modulation doping to control the high-density electron gas at a polar/non-polar oxide interface. Appl. Phys. Lett. 101:111604 [Google Scholar]
  55. Moetakef P, Jackson CA, Hwang J, Balents L, Allen SJ, Stemmer S. 55.  2012. Toward an artificial Mott insulator: correlations in confined high-density electron liquids in SrTiO3. Phys. Rev. B 86:201102(R) [Google Scholar]
  56. Cain TA, Lee S, Moetakef P, Balents L, Stemmer S, Allen SJ. 56.  2012. Seebeck coefficient of a quantum confined, high-electron-density electron gas in SrTiO3. Appl. Phys. Lett. 100:161601 [Google Scholar]
  57. Tokura Y, Taguchi Y, Okada Y, Fujishima Y, Arima T. 57.  et al. 1993. Filling dependence of electronic properties on the verge of metal-Mott-insulator transition in Sr1−xLaxTiO3. Phys. Rev. Lett. 70:2126–29 [Google Scholar]
  58. Conti G, Kaiser AM, Gray AX, Nemsak S, Palsson GK. 58.  et al. 2013. Band offsets in complex-oxide thin films and heterostructures of SrTiO3/LaNiO3 and SrTiO3/GdTiO3 by soft and hard X-ray photoelectron spectroscopy. J. Appl. Phys. 113:143704 [Google Scholar]
  59. Qiao L, Droubay TC, Kaspar TC, Sushko PV, Chambers SA. 59.  2011. Cation mixing, band offsets and electric fields at LaAlO3/SrTiO3(001) heterojunctions with variable La:Al atom ratio. Surf. Sci. 605:1381–87 [Google Scholar]
  60. Noguera C.60.  2000. Polar oxide surfaces. J. Phys. Condens. Matter 12:R367–410 [Google Scholar]
  61. Tasker PW.61.  1979. Stability of ionic crystal surfaces. J. Phys. C 12:4977–84 [Google Scholar]
  62. Bristowe NC, Littlewood PB, Artacho E. 62.  2011. Surface defects and conduction in polar oxide heterostructures. Phys. Rev. B 83:205405 [Google Scholar]
  63. Bi F, Bogorin DF, Cen C, Bark CW, Park JW. 63.  et al. 2010. “Water-cycle” mechanism for writing and erasing nanostructures at the LaAlO3/SrTiO3 interface. Appl. Phys. Lett. 97:173110 [Google Scholar]
  64. Siemons W, Koster G, Yamamoto H, Harrison WA, Lucovsky G. 64.  et al. 2007. Origin of charge density at LaAlO3 on SrTiO3 heterointerfaces: possibility of intrinsic doping. Phys. Rev. Lett. 98:196802 [Google Scholar]
  65. Chambers SA.65.  2011. Understanding the mechanism of conductivity at the LaAlO3/SrTiO3(001) interface. Surf. Sci. 605:1133–40 [Google Scholar]
  66. Schlom DG, Mannhart J. 66.  2011. Oxide electronics: Interface takes charge over Si. Nat. Mater. 10:168–69 [Google Scholar]
  67. Chen YZ, Christensen DV, Trier F, Pryds N, Smith A, Linderoth S. 67.  2012. On the origin of metallic conductivity at the interface of LaAlO3/SrTiO3. Appl. Surf. Sci. 258:9242–45 [Google Scholar]
  68. Kalabukhov A, Gunnarsson R, Borjesson J, Olsson E, Claeson T, Winkler D. 68.  2007. Effect of oxygen vacancies in the SrTiO3 substrate on the electrical properties of the LaAlO3/SrTiO3 interface. Phys. Rev. B 75:121404 [Google Scholar]
  69. Chen YZ, Pryds N, Kleibeuker JE, Koster G, Sun JR. 69.  et al. 2011. Metallic and insulating interfaces of amorphous SrTiO3-based oxide heterostructures. Nano Lett. 11:3774–78 [Google Scholar]
  70. Posadas AB, Lippmaa M, Walker FJ, Dawber M, Ahn CH, Triscone J-M. 70.  2007. Growth and novel applications of epitaxial oxide thin films. Physics of Ferroelectrics: A Modern Perspective KM Rabe, CH Ahn, J-M Triscone 105219–304 Berlin: Springer-Verlag [Google Scholar]
  71. Chambers SA.71.  2010. Epitaxial growth and properties of doped transition metal and complex oxide films. Adv. Mater. 22:219–48 [Google Scholar]
  72. Cuomo JJ, Pappas DL, Bruley J, Doyle JP, Saenger KL. 72.  1991. Vapor deposition processes for amorphous carbon films with sp3 fractions approaching diamond. J. Appl. Phys. 70:1706–11 [Google Scholar]
  73. Ohnishi T, Shibuya K, Yamamoto T, Lippmaa M. 73.  2008. Defects and transport in complex oxide thin films. J. Appl. Phys. 103:103703 [Google Scholar]
  74. Dhote AM, Meier AL, Towner DJ, Wessels BW, Ni J, Marks TJ. 74.  2005. Low temperature deposition of epitaxial BaTiO3 films in a rotating disk vertical MOCVD reactor. J. Vac. Sci. Technol. B 23:1674–78 [Google Scholar]
  75. Teren AR, Belot JA, Edleman NL, Marks TJ, Wessels BW. 75.  2000. MOCVD of epitaxial BaTiO3 films using a liquid barium precursor. Chem. Vapor Depos. 6:175–77 [Google Scholar]
  76. Boyd DA, Hirsch SG, Hubbard C, Cole MW. 76.  2009. BST films grown by metal organic chemical vapor deposition incorporating real-time control of stoichiometry. Integr. Ferroelectr. 111:17–26 [Google Scholar]
  77. VanBuskirk PC, Bilodeau SM, Roeder JF, Kirlin PS. 77.  1996. Metalorganic chemical vapor deposition of complex metal oxide thin films by liquid source chemical vapor deposition. Jpn. J. Appl. Phys. 35:2520–25 [Google Scholar]
  78. Wessels BW.78.  1995. Metal-organic chemical vapor deposition of ferroelectric oxide thin films for electronic and optical applications. Annu. Rev. Mater. Sci. 25:525–46 [Google Scholar]
  79. Hellman ES, Hartford EH. 79.  1994. Effects of oxygen on the sublimation of alkaline earths from effusion cells. J. Vac. Sci. Technol. B 12:1178–80 [Google Scholar]
  80. Theis CD, Schlom DG. 80.  1996. Cheap and stable titanium source for use in oxide molecular beam epitaxy systems. J. Vac. Sci. Technol. A 14:2677–79 [Google Scholar]
  81. Berkley DD, Johnson BR, Anand N, Beauchamp KM, Conroy LE. 81.  et al. 1988. In situ formation of superconducting YBa2Cu3O7−x thin films using pure ozone vapor oxidation. Appl. Phys. Lett. 53:1973–75 [Google Scholar]
  82. Jalan B, Engel-Herbert R, Wright NJ, Stemmer S. 82.  2009. Growth of high-quality SrTiO3 films using a hybrid molecular beam epitaxy approach. J. Vac. Sci. Technol. A 27:461–64 [Google Scholar]
  83. Tsao JY.83.  1993. Materials Fundamentals of Molecular Beam Epitaxy Boston: Academic [Google Scholar]
  84. Theis CD, Yeh J, Schlom DG, Hawley ME, Brown GW. 84.  1998. Adsorption-controlled growth of PbTiO3 by reactive molecular beam epitaxy. Thin Solid Films 325:107–14 [Google Scholar]
  85. Lee JH, Ke X, Misra R, Ihlefeld JF, Xu XS. 85.  et al. 2010. Adsorption-controlled growth of BiMnO3 films by molecular-beam epitaxy. Appl. Phys. Lett. 96:262905 [Google Scholar]
  86. Jalan B, Moetakef P, Stemmer S. 86.  2009. Molecular beam epitaxy of SrTiO3 with a growth window. Appl. Phys. Lett. 95:032906 [Google Scholar]
  87. Haeni JH, Theis CD, Schlom DG. 87.  2000. RHEED intensity oscillations for the stoichiometric growth of SrTiO3 thin films by reactive molecular beam epitaxy. J. Electroceram. 4:385–91 [Google Scholar]
  88. Klausmeier-Brown ME, Eckstein JN, Bozovic I, Virshup GF. 88.  1992. Accurate measurement of atomic beam flux by pseudo double beam atomic absorption spectroscopy for growth of thin film oxide superconductors. Appl. Phys. Lett. 60:657–59 [Google Scholar]
  89. Jalan B, Engel-Herbert R, Cagnon J, Stemmer S. 89.  2009. Growth modes in metal-organic molecular beam epitaxy of TiO2 on r-plane sapphire. J. Vac. Sci. Technol. A 27:230–33 [Google Scholar]
  90. Moetakef P, Zhang JY, Raghavan S, Kajdos AP, Stemmer S. 90.  2013. Growth window and effect of substrate symmetry in hybrid molecular beam epitaxy of a Mott insulating rare earth titanate. J. Vac. Sci. Technol. A 31:041503 [Google Scholar]
  91. Son J, Moetakef P, Jalan B, Bierwagen O, Wright NJ. 91.  et al. 2010. Epitaxial SrTiO3 films with electron mobilities exceeding 30,000 cm2 V−1 s−1. Nat. Mater. 9:482–84 [Google Scholar]
  92. Allen SJ, Jalan B, Lee S, Ouellette DG, Khalsa G. 92.  et al. 2013. Conduction-band edge and Shubnikov–de Haas effect in low-electron-density SrTiO3. Phys. Rev. B 88:045114 [Google Scholar]
  93. Cain TA, Kajdos AP, Stemmer S. 93.  2013. La-doped SrTiO3 films with large cryogenic thermoelectric power factors. Appl. Phys. Lett. 102:182101 [Google Scholar]
  94. Keeble DJ, Jalan B, Ravelli L, Egger W, Kanda G, Stemmer S. 94.  2011. Suppression of vacancy defects in epitaxial La-doped SrTiO3 films. Appl. Phys. Lett. 99:232905 [Google Scholar]
  95. Jalan B, Allen SJ, Beltz GE, Moetakef P, Stemmer S. 95.  2011. Enhancing the electron mobility of SrTiO3 with strain. Appl. Phys. Lett. 98:132102 [Google Scholar]
  96. Biscaras J, Bergeal N, Kushwaha A, Wolf T, Rastogi A. 96.  et al. 2010. Two-dimensional superconductivity at a Mott insulator/band insulator interface LaTiO3/SrTiO3. Nat. Commun. 1:89 [Google Scholar]
  97. Annadi A, Putra A, Srivastava A, Wang X, Huang Z. 97.  et al. 2012. Evolution of variable range hopping in strongly localized two dimensional electron gas at NdAlO3/SrTiO3 (100) heterointerfaces. Appl. Phys. Lett. 101:231604 [Google Scholar]
  98. Chen YZ, Bovet N, Trier F, Christensen DV, Qu FM. 98.  et al. 2013. A high-mobility two-dimensional electron gas at the spinel/perovskite interface of γ-Al2O3/SrTiO3. Nat. Commun. 4:1371 [Google Scholar]
  99. Mattheis LF.99.  1972. Energy bands for KNiF3, SrTiO3, KMoO3, and KTaO3. Phys. Rev. B 6:4718–40 [Google Scholar]
  100. Mattheiss LF.100.  1972. Effect of the 110°K phase transition on the SrTiO3 conduction bands. Phys. Rev. B 6:4740–53 [Google Scholar]
  101. Tsuda K, Tanaka M. 101.  1995. Refinement of crystal structure parameters using convergent-beam electron diffraction: the low-temperature phase of SrTiO3. Acta Crystallogr. A 51:7–19 [Google Scholar]
  102. Uwe H, Sakudo T, Yamaguchi H. 102.  1985. Interband electronic Raman scattering in SrTiO3. Jpn. J. Appl. Phys. 24:Suppl. 24-2519–21 [Google Scholar]
  103. Uwe H, Yoshizaki R, Sakudo T, Izumi A, Uzumaki T. 103.  1985. Conduction band structure of SrTiO3. Jpn. J. Appl. Phys. 24:Suppl. 24-2335–37 [Google Scholar]
  104. Janotti A, Steiauf D, Van de Walle CG. 104.  2011. Strain effects on the electronic structure of SrTiO3: toward high electron mobilities. Phys. Rev. B 84:201304 [Google Scholar]
  105. van Mechelen JLM, van der Marel D, Grimaldi C, Kuzmenko AB, Armitage NP. 105.  et al. 2008. Electron-phonon interaction and charge carrier mass enhancement in SrTiO3. Phys. Rev. Lett. 100:226403 [Google Scholar]
  106. Stern F.106.  1972. Self-consistent results for n-type Si inversion layers. Phys. Rev. B 5:4891–99 [Google Scholar]
  107. Thiel S, Hammerl G, Schmehl A, Schneider CW, Mannhart J. 107.  2006. Tunable quasi-two-dimensional electron gases in oxide heterostructures. Science 313:1942–45 [Google Scholar]
  108. Rakhmilevitch D, Neder I, Ben Shalom M, Tsukernik A, Karpovski M. 108.  et al. 2013. Anomalous response to gate voltage application in mesoscopic LaAlO3/SrTiO3 devices. Phys. Rev. B 87:125409 [Google Scholar]
  109. Bell C, Harashima S, Kozuka Y, Kim M, Kim BG. 109.  et al. 2009. Dominant mobility modulation by the electric field effect at the LaAlO3/SrTiO3 interface. Phys. Rev. Lett. 103:226802 [Google Scholar]
  110. Caviglia AD, Gariglio S, Reyren N, Jaccard D, Schneider T. 110.  et al. 2008. Electric field control of the LaAlO3/SrTiO3 interface ground state. Nature 456:624–27 [Google Scholar]
  111. Boucherit M, Shoron OF, Cain TA, Jackson CA, Stemmer S, Rajan S. 111.  2013. Extreme charge density SrTiO3/GdTiO3 heterostructure field effect transistors. Appl. Phys. Lett. 102:242909 [Google Scholar]
  112. Altarelli M, Ekenberg U, Fasolino A. 112.  1985. Calculations of hole subbands in semiconductor quantum wells and superlattices. Phys. Rev. B 32:5138–43 [Google Scholar]
  113. Broido DA, Sham LJ. 113.  1985. Effective masses of holes at GaAs-AlGaAs heterojunctions. Phys. Rev. B 31:888–92 [Google Scholar]
  114. Neville RC, Hoeneisen B, Mead CA. 114.  1972. Permittivity of strontium titanate. J. Appl. Phys. 43:2124–31 [Google Scholar]
  115. Khalsa G, MacDonald AH. 115.  2012. Theory of the SrTiO3 surface state two-dimensional electron gas. Phys. Rev. B 86:125121 [Google Scholar]
  116. Park SY, Millis AJ. 116.  2013. Charge density distribution and optical response of the LaAlO3/SrTiO3 interface. Phys. Rev. B 87:205145 [Google Scholar]
  117. Popovic ZS, Satpathy S. 117.  2005. Wedge-shaped potential and Airy-function electron localization in oxide superlattices. Phys. Rev. Lett. 94:176805 [Google Scholar]
  118. Pentcheva R, Pickett WE. 118.  2007. Correlation-driven charge order at the interface between a Mott and a band insulator. Phys. Rev. Lett. 99:016802 [Google Scholar]
  119. Son WJ, Cho E, Lee B, Lee J, Han S. 119.  2009. Density and spatial distribution of charge carriers in the intrinsic n-type LaAlO3-SrTiO3 interface. Phys. Rev. B 79:245411 [Google Scholar]
  120. Delugas P, Filippetti A, Fiorentini V, Bilc DI, Fontaine D, Ghosez P. 120.  2011. Spontaneous 2-dimensional carrier confinement at the n-type SrTiO3/LaAlO3 interface. Phys. Rev. Lett. 106:166807 [Google Scholar]
  121. Khalsa G, Lee B, MacDonald AH. 121.  2013. Theory of t2g electron-gas Rashba interactions. Phys. Rev. B 88:041302(R) [Google Scholar]
  122. Zhong ZC, Toth A, Held K. 122.  2013. Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces. Phys. Rev. B 87:161102 [Google Scholar]
  123. Zhong ZC, Zhang QF, Held K. 123.  2013. Quantum confinement in perovskite oxide heterostructures: tight binding instead of a nearly free electron picture. Phys. Rev. B 88:125401 [Google Scholar]
  124. Lechermann F, Boehnke L, Grieger D. 124.  2013. Formation of orbital-selective electron states in LaTiO3/SrTiO3 superlattices. Phys. Rev. B 87:241101 [Google Scholar]
  125. Chen HH, Kolpak A, Ismail-Beigi S. 125.  2010. First-principles study of electronic reconstructions of LaAlO3/SrTiO3 heterointerfaces and their variants. Phys. Rev. B 82:085430 [Google Scholar]
  126. Lee J, Demkov AA. 126.  2008. Charge origin and localization at the n-type SrTiO3/LaAlO3 interface. Phys. Rev. B 78:193104 [Google Scholar]
  127. Popovic ZS, Satpathy S, Martin RM. 127.  2008. Origin of the two-dimensional electron gas carrier density at the LaAlO3 on SrTiO3 interface. Phys. Rev. Lett. 101:256801 [Google Scholar]
  128. Santander-Syro AF, Copie O, Kondo T, Fortuna F, Pailhes S. 128.  et al. 2011. Two-dimensional electron gas with universal subbands at the surface of SrTiO3. Nature 469:189–93 [Google Scholar]
  129. Chang YJ, Moreschini L, Bostwick A, Gaines GA, Kim YS. 129.  et al. 2013. Layer-by-layer evolution of a two-dimensional electron gas near an oxide interface. Phys. Rev. Lett. 111:126401 [Google Scholar]
  130. Smoliner J, Berthold G, Strasser G, Gornik E, Weimann G, Schlapp W. 130.  1990. Subband spectroscopy in two-dimensional electron gas systems. Semicond. Sci. Technol. 5:308–11 [Google Scholar]
  131. Demmerle W, Smoliner J, Berthold G, Gornik E, Weimann G, Schlapp W. 131.  1991. Tunneling spectroscopy in barrier-separated two-dimensional electron-gas systems. Phys. Rev. B 44:3090–104 [Google Scholar]
  132. Raghavan S, Allen SJ, Stemmer S. 132.  2013. Subband structure of two-dimensional electron gases in SrTiO3. Appl. Phys. Lett. 103:212103 [Google Scholar]
  133. Hosoda M, Hikita Y, Hwang HY, Bell C. 133.  2013. Transistor operation and mobility enhancement in top-gated LaAlO3/SrTiO3 heterostructures. Appl. Phys. Lett. 103:103507 [Google Scholar]
  134. Hirakawa K, Sakaki H, Yoshino J. 134.  1985. Mobility modulation of the two-dimensional electron gas via controlled deformation of the electron wave function in selectively doped AlGaAs-GaAs heterojunctions. Phys. Rev. Lett. 54:1279–82 [Google Scholar]
  135. Joshua A, Ruhman J, Pecker S, Altman E, Ilani S. 135.  2013. Gate-tunable polarized phase of two-dimensional electrons at the LaAlO3/SrTiO3 interface. Proc. Natl. Acad. Sci. USA 110:9633–38 [Google Scholar]
  136. Caviglia AD, Gabay M, Gariglio S, Reyren N, Cancellieri C, Triscone J-M. 136.  2010. Tunable Rashba spin-orbit interaction at oxide interfaces. Phys. Rev. Lett. 104:126803 [Google Scholar]
  137. Fete A, Gariglio S, Caviglia AD, Triscone J-M, Gabay M. 137.  2012. Rashba induced magnetoconductance oscillations in the LaAlO3-SrTiO3 heterostructure. Phys. Rev. B 86:201105(R) [Google Scholar]
  138. Gabay M, Gariglio S, Triscone J-M, Santander-Syro AF. 138.  2013. 2-Dimensional oxide electronic gases: interfaces and surfaces. Eur. Phys. J. 222:1177–83 [Google Scholar]
  139. Joshua A, Pecker S, Ruhman J, Altman E, Ilani S. 139.  2012. A universal critical density underlying the physics of electrons at the LaAlO3/SrTiO3 interface. Nat. Commun. 3:1129 [Google Scholar]
  140. Moetakef P, Ouellette DG, Williams JR, Allen SJ, Balents L. 140.  et al. 2012. Quantum oscillations from a two-dimensional electron gas at a Mott/band insulator interface. Appl. Phys. Lett. 101:151604 [Google Scholar]
  141. Ben Shalom M, Ron A, Palevski A, Dagan Y. 141.  2010. Shubnikov–de Haas oscillations in SrTiO3/LaAlO3 interface. Phys. Rev. Lett. 105:206401 [Google Scholar]
  142. Caviglia AD, Gariglio S, Cancellieri C, Sacepe B, Fete A. 142.  et al. 2010. Two-dimensional quantum oscillations of the conductance at LaAlO3/SrTiO3 interfaces. Phys. Rev. Lett. 105:236802 [Google Scholar]
  143. Huijben M, Koster G, Molegraaf HJA, Kruize MK, Wenderich S. 143.  et al. 2010. High mobility interface electron gas by defect scavenging in a modulation doped oxide heterostructure. arXiv:1008.1896v1 [cond-mat.mtrl-sci]
  144. Ben Shalom M, Sachs M, Rakhmilevitch D, Palevski A, Dagan Y. 144.  2010. Tuning spin-orbit coupling and superconductivity at the SrTiO3/LaAlO3 interface: a magnetotransport study. Phys. Rev. Lett. 104:126802 [Google Scholar]
  145. Fidkowski L, Jiang HC, Lutchyn RM, Nayak C. 145.  2013. Magnetic and superconducting ordering in one-dimensional nanostructures at the LaAlO3/SrTiO3 interface. Phys. Rev. B 87:014436 [Google Scholar]
  146. Nakamura H, Koga T, Kimura T. 146.  2012. Experimental evidence of cubic Rashba effect in an inversion-symmetric oxide. Phys. Rev. Lett. 108:206601 [Google Scholar]
  147. Chen R, Lee S, Balents L. 147.  2013. Dimer Mott insulator in an oxide heterostructure. Phys. Rev. B 87:161119(R) [Google Scholar]
  148. Jackson CA, Stemmer S. 148.  2013. Interface-induced magnetism in perovskite quantum wells. Phys. Rev. B 88:180403(R) [Google Scholar]
  149. Ouellette DG, Moetakef P, Cain TA, Zhang JY, Stemmer S. 149.  et al. 2013. High-density two-dimensional small polaron gas in a delta-doped Mott insulator. Sci. Rep. 3:3284 [Google Scholar]
  150. Zhang JY, Hwang J, Raghavan S, Stemmer S. 150.  2013. Symmetry lowering in extreme-electron-density perovskite quantum wells. Phys. Rev. Lett. 110:256401 [Google Scholar]
/content/journals/10.1146/annurev-matsci-070813-113552
Loading
/content/journals/10.1146/annurev-matsci-070813-113552
Loading

Data & Media loading...

  • Article Type: Review Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error